Kalu Omokorie Obasi (Professor of Environmental Health and Toxicology)
H.O.D , Environmental Management and Toxicology (EMT)
Michael Okpara University of Agriculture Umudike (MOUAU)
Kalu studied Applied Biology at Nnamdi Azikiwe University, Awka ( former ASUTECH). He
proceeded to Federal University of Technology, Owerri (FUTO), where he did his Masters
degree and Doctor of Philosophy in Environmental Health Biology. Kalu is a registered
and licensed Environmental Health Scientist (Licenced by Environmental Health Officers
Registration Council of Nigeria- EHORECON). He is a member, Chartered Institute of
Environment Health ( London). Kalu is a member of Institute of Safety Professionals of
Nigeria (ISPON) and currently, the ISPON Patron in Abia State. Kalu was a participant at
the” Consultative Stakeholders Meeting on the Implementation of Environmental Audit
Programmes in Nigeria”, organized by Fed. Min. of Environment; held in 2001 at B-Bek
Plaza PortHarcourt. He was once a keynote speaker at World Environment day at Abuja
(Transcorp Hotels and Towers). Kalu was a consultant for Abia State House Committee
on Environment 2009. He was equally a member of team of accredited Consultants by
Federal Ministry of Environment in the aspect of Pest Control. Kalu has been engaged by
the EHORECON as a Resource person in their Mandatory Continuing Education
Programme- a programme that has taken Kalu to all parts of Nigeria. Kalu was a
recipient of the most committed Teaching Staff Award of College of Natural Resources
and Environmental Management in 2018 at MOUAU. Kalu was a recipient of TETFund
/National Research Fund Award 2018 , Prinncipal researcher of ‘ Health Hazards and
Bioconcentration Factors of Endocrine Disrupting Chemicals and Heavy Metals in
Shellfish from Rivers of South South Nigeria’. Kalu is the Editor in Chief of Journal of
Environmental Health (JEH). Kalu has been the Pro-tem President, Society for
Environmental Health of Nigeria (SEHON), 2014 till date. Kalu is the President of
‘Climatesane International’ an international NGO. Kalu was appointed the Subject Matter
Expert in ‘ Environmental Concepts in Public Health’ by Texilla American University 2014.
Kalu has vast administrative experience as a lecturer which include: course advisership
(FUTO and MOUAU), Examinations officer (FUTO), undergraduate seminar and projects
coordinator (FUTO), Time table officer (FUTO), Research committee member (FUTO),
University Laboratory Equipment Inventory Committee ( MOUAU), Member MOUAU Senate
Business Committee(SBC) 2017-2020, Member MOUAU Senate Special Committee on
Results Consideration, 2017-2020. Member, University Admission Board (UAB) MOUAU
2018-2023 , College Servicom Window(MOUAU), College Representative at MOUAU
Senate, Postgraduate programmes coordinator ( EMT dept MOUAU) and currently, Head
of Department of Environmental Management and Toxicology(EMT), etc. Kalu has over
fifty publications in referred journals spread across the globe: Asia, USA, Africa, Europe
etc.
Kalu started lecturing career at Imo State University, Owerri; Centre for Continuing
Education (CEC) in 2002. Kalu was part of the team that started the Professional Public
Health Programme of Imo State University. Kalu secured a tenure appointment with
Federal University of Technology, Owerri in February 2005 as an Assistant lecturer in the
department of Molecular Biology. Through hard work and high level of commitment to
assignments, Kalu rose by rank to Senior lecturer in FUTO(rendering lecturing services in
Departments of Molecular Biology, Biotechnology, Biological Science and Public Health
Technology) . Kalu got appointment at Michael Okpara University of Agriculture in 2015,
however; after the statutory three months notice of service transfer, started work at
Umudike in February 2016. Besides the core area of specialization, Kalu has a training in
accountancy, electronic data processing etc. Kalu has supervised over forty Masters
degree graduates (M.Sc and MPH) plus five Ph.D graduates.
Journal Articles/ Published Papers In Referred Journals
1. Obasi K.O.and M.O.E Iwuala, (2004); Biochemical analysis of Aba River
Enrichment (based on phosphate and nitrate indices) in relation to Escherichia coli
counts; International Journal of Env.Health and Human Dev. Vol. 5 (no.l).
2. Okereke J.N, Obiekezie S.O and K.O. Obasi (2007). Microbial floral of oil-spilled
sites in Egbema,Imo State African Journal of Biotechnology volm 6(8)pp xxx-xxx.
http://www.academicjoumals.org/AJB
3. Okereke J.N, Obasi, K.O, Obiekezie S.O and Okechukwu .R (2006).Bacterial
quality of rainwater in selected communities of Imo State.Nigeria. Estud.
Biol.Brazil. v.28 no 63 pg 51-
59.http://periodicos.pucpr.br/index.php/estudosdebiologia/article/view/22723
4. Obasi K.O ,A.C. Udebuani and J.N. Okereke (2006). Study on the Relationships
Between the Chemical Oxygen Demand and Total Aerobic Fungi and Bacteria in
Aba River,Abia State. Journal of Research in Bioscience. volm.2(l)
5. Obasi, Kalu O (2006). Biology Update. Rurnok printing and publishing house Aba.
(1st edition) ISBN. 978-30560-9-3.
6. J.N.Okereke, K. O Obasi. R.I Okechukwu and M.C. Nnoli (2006). Physicochemical and
Bacteriological Quality of Rain Water in Egbemba, Imo State Nigeria. International
Journal of Natural and Applied Science, volm, 2no 4pg372-
376.http://www.ajol.info/index.php/ijonas/issue/view/5168
7. Okereke J.N; Nnoli M.C, Obasi,K.O,and Ukegbu C.P(2007): Genetically engineered food
crops: prospects and problems-a review. Int.J. Biotechnol and Applied Science 2(3):261-
265.ISSN: 1597-9784. http://ijobas.org
8. K .O .Obasi, M . O . E. Iwuala, H.C. Nwigwe, J.N. Ogbulie , A.C. Udebuani (2008):
comparative study on the concentration of Trioxonitrate (v) ions in five selected rivers of
Abia State, Nigeria. International Journal of Environmental Health and Human
Development. Lol.6(no.2)pp 19/20.
9. K. O. Obasi, M.O.E. Iwuala, H.C. Nwigwe and J.N. Okereke (2008): Study on the
Concentration of mercury in selected rivers of Abia State, Nigeria. International Journal of
Environmental Health and Human Development. Vol.9 (no.l)
10. K.O.Obasi, J.N.Okereke and R.I. Okechukwu (2009): A study on the relationships beween
nitrate ion and chemical oxygen demand (COD) in five selected rivers of Abia State,
Nigeria. Institute of Ecology and Environmental studies, Obafemi Awolowo University, lle-
ife , Nigeria vol.2 (145/150)
11. K.O.Obasi, N.C. Chineze and M.C.Duru, (2009). Studies on the bacteriocidal effects of
garlic (Allium sativum Linn) on selected pathogenic bacteria International Journal of
Environmental Health and Human Development Vol. 10(2)
12. K.O.Obasi, N.C. Chineze (2009). Studies on the antimicrobial effects of gvngQT(Zingiber
officinale Roscoe) on selected pathogenic bacteria. International Journal of Environmental
Health and Human Development Vol. 10(1)
13. Okechukwu. R.I., Okereke J.N;Ezejiofor T.I.N; Obasi, K.O. and Ebere G.O (2011).
Relationship between malaria vector densities in artificial container habitat, land use
changes and temperature. Nigerian Journal of Parasitology, Vol. 32(2) pp283-286. ISSN
11174145.http://www.ajol.info/index.php/njpar/issue/view/10772
14. Okechukwu R.I., Tony Egboka N.A, Okechi R.N. and Obasi K.O (2011). Studies on the
proximate and mineral composition of ‘BURUKUTU’ and ‘KUNU’ – two Nigerian
fermented food drinks. Journal of Science and Technology Research , Vol. 10 (3). ISSN
1596-9646
15. R.I.Okechukwu, K.O.Obasi, M.C.Nnoli and A.A.Ukaoma (2010). Antimicrobial properties
and preliminary phytochemical analysis of Carica papaya leaf. Advances in Science and
Technology,Vol. 4(1).
16. K.O.Obasi, (2012). The Characteristics of living organisms in Foundation Biology for
University Students (Edited by M.O.E Iwuala, RJ.Okechukwu and I.A.Okwujiako).Dept. of
Biological Science, Fed. Umv. of Tech, Ovverri. ISBN: 978-219-314-3
17. K.O.Obasi,N.D.Ijere and R.I.Okechukwu (2013). Species Diversity and Equitability
Indices of Some Fresh Water Species in Aba River and Azumini Blue River, Abia State
Nigeria International Journal of Science and Technology’ U.K VoL 2 (3). www.iournalof
sciences-technology .org/archive/2013/march. vol_2_no3/march
18. K,Q,Obasi,RJ.Okechukwu and NJ.Nwakocha, (2013)-,Species Diversity and Evenness of
Some Organisms in Usumani and Imo Rivers, Abia State Nigeria. International Journal of
Science and Technology U.K Vol. 2 (9) www.iournalof sciences-
technology,org/archive/20I13/sept_vol_2_no_9/sep_2013
19. Okereke J.N, Obasi,K.O, Udensi J.U and Ahumibe N.C(2013). Studies on the Effect of
Burnt Naira Ash on Soil Properties, Natural Products Research Bulletin(2Q] 3)1 (2):
034:040,
20. Okereke J.N, Okereke C.B.N, Obasi K.O and Nnoli M.C(2013). Survey on the distribution
and prevalence of water related diseases in Owerri from 2005 – 2008. Int. Journal of
Biotech and Allied Science, 8(1): 1024-1030 ISSN 1597-9784
21. Kalu. O .Obasi, E.A. Nwoke and F.N.K Obasi(2014). Handbook of Health Information
System, Prestige Press and Publising Company, Aba ISBN: 978-978-53232-69
22. Udebuani A.C, Abara P.C, Obasi K.0 and Okuh S.U(2015). Studies on the insecticidal
properties of Chromolaena odorata{Asteraceae) against adult stage of Periplanata
Americana Journal of Entomology and Zoology Studies 2015;3(lJ:xx-xx, E-ISSN:2320-
7Q78 P-SSN:2349-6800. www.entomolioumal.com
23. Kalu.Q,Obasi, Kalu, Chinedu, Okereke,J.N,Udebuani, A.C, Ezeyi, E.U and Anyadoh
S.N(2015).Study on concentrations of selected heavy metals: cadmium(Cd), lead(Pb),
aesenic(As) and mercury(Hg) in the soft tissue of periwinkle (Tympanotonus fuscatusVar.
radula) harvested from Brass Island River, Bayelsa State; Nigeria. International Journal of
Science and Technology U.K Vol. 4 (10). www.iournalof sciences-
technology.org/archive/201 5/oct.vol_4_l 0/oct_2015
24. Kalu.O.Obasi, Kalu, Chinedu, Okereke,J.N,Udebuani, A.C, Ezeji, E.U and Anyadoh ,
S.N(2015). Concentrations of: cadmium(Cd), lead(Pb),arsenic(As) and mercury(Hg) in the
soft tissue of peri wink! e( Tympanotonus fuscatus Var, radula) harvested from Eagle Island
River, Rivers State; Nigeria. International Journal of Science and Technology U.K Vol. 2
(9). www.journalofsciences-technology.org/archive/2015/oct_. vol_4_l0/oct_20l5
25. Kalu.O.Obasi, Enemchukwu, S. Okereke,J.N, Ezeji, E.U and Oparaigbo, M.I
(2015).Analysis of heavy metals concentration in Frawa (Macrobrachium sp) harvested
from Gberikoko river. Delta State Nigeria International Journal of Science and Technology
India Vol. 3 issue 8,(Pg 285-288) ISSN 2321-919X, www.theijst.com
26. Kalu.O.Obasi, Enemchukwu, S, Udebuani, A.C , Oparaigbo, M.I and Ezea,C.O
(2015).Heavy metals concentration in Prawn(Macrobrachium sp) harvested from Oron
river, Akwa Ibom State Nigeria International Journal of Science and Technology India
VoL 3 issue 8.(Pg 280-284)ISSN 2321-919X. www.theijst.com
27. Okereke, J.N,Obasi, K.O, Any adoh-Nwadike, S. 0, Ezeji, E.U and
Udebuani,A.C(2015).Geohelminthes Associated with Geophagic Pupils in Selected
Primary Schools in Oyi, Anambra State. Science Journal of Public Health, USA :Vol 3
issue 5-1 Pages 45-50.sciencepublishinggroup.com
28. Okereke, J.N, Udebuani, A.C, Ezeji. E.U, Obasi, K.O andNnoli, M.C (2015). Possible
Health Implications Associated with Cosmetics: A Review.
http://www, sciencepublishinggroup.com/journal/paperinfo.aspx?
journalid=251&doi=10.11648/j. siph.s.2015030501.21DOI:
10.11648/i.sjph.s.2015030501.21
29. Anyadoh-Nwadike, S.O, Okereke J.N, Odah,R, Qbijekwu O., Okorondu S.I and Obasi,
K.O.(2015). Bacteriological Quality of Water Contaminated with Faecal Waste from
Livestock. Science Journal of Public Health USA 2015: 3(5-l):29-33. ISSN: 2328-
7942(print) ISSN: 2328- 7950(online). sciencepub3ishinggroup.com
30. Udebuani, A.C. Obasi,K.O, Okereke, J.N, Ezeji, E.U, (2015).Effects of Anthropogenic
activities on soil carbon storage and compactness in coastal plain soil of tropical urban area
International Journal of Science and Engineering Research (IJSEP.). ISSN 2229-5518
31. Kalu O. Obasi, Emeaghara U, Udebuani, A.C, Okereke, J.N and Oparaigbo .M.I (2016).
The antimicrobial effects of local spices : onions (allium cepa, garlic (allium sativum),
gmger (zingiber officinale), and pepper(piper guineense) on selected pathogenic bacteria
and fungus, International Journal of Science and Technology India ISSN 2321-919X.
www.theijst.com
32. Ethelbert. U.E, Angela C.U, Josephat Q, Sylvia . A.N, Skechukwu N.E.O and Kalu
O(2015).Layer Performance and Egg Quality of Poultry Birds Exposed to Dichlorvos.
Journal of Environmental Chemistry and Ecotoxicology. Vol. x(x),pp. xxx-xxx,xxxxxxxxxx
2015. DOI: 1Q.5897/JECE 2015.0354. Article number: xxxxxxxxxxxx.SSSN 2141-226X,
http://doi.org/l0.5897/JJECE2Q15.0354 or http://www.academjcjournals.org/JECE
33. Ethelbert. U.E, Oluchi. D.O, Angela C.U, Josephat O, and Kalu O. Obasi (2015). Effect of
Dichlorvos on the fertility of adult male albino rats.Atotwe and Science 2015; 13{12):l-5.
ISSN: 1545-0740. http://www. Sciencepub.net/nature 1. Dpi: lQ.7537/marsnsjl31215.01
34. Okereke, J.N, Ogidi, O.I and Obasi, K.O, (2016).Removal of Inorganic Anions in Brewery
Effluent using Banana Pee/s.lnternational Journal of Advanced Research in Biological
Sciences.ISSN: 2348-8069. Vol.3, issue 6-2016 pg 192-197.SOI: http://s-o-i-
org/1.15/ijarbs-2016-3-6-2
35. J.N.Okereke,O.I.Ogidi and K.O.Obasi (2016). Environmental and Health Impact of
Industrial Wastewater Effluents in Nigeria- A. Review, International Journal of Advanced
Research in Biological Sciences. ISSN: 2348-8069. Vol.3, issue 6-2016. Pg 55-
67.SOI:http://s-o-i- org/ 1.15/ijarbs-3-6-8.
36. Okereke, J.N., Ogidi, O.l and Obasi, K.0(2016). Biosorption of Cadmium and lead in
textile effluent using Musa sapientum (banana) peels. International Journal of Science and
Technology India .ISSN 2321-919X. www.theijst.com
37. Obasi, K,0, Qnwubrko, P and Ogbonna P.G (2017). Effects of photographic effluent on
total heterotrophic bacteria and fungi in Qua-lboe river, Ikwuano LGA, Abia State.
Foundation for African Development through International Biotechnology (FADIB)
Proceedings Vol. 23,85-90 (2017)
38. Uchenna, I, Obasi, K.O and Ogbonna P.C (2017). Microbial and Biochemical Qualities of
Vendor Dispensed Food- African Salad( abacha) from Five Sub-Urban Areas of Owerri,
Imo State. Foundation for African Development through International Biotechnology
(FADIB) Proceedings Vol. 23, 47-52(2017)
39. Obasi, K.O, Monday, A.M, Ogbonna P.C (2017). Toxic effects of brewery effluent on
Clarias gariepinus. Foundation for African Development through International
Biotechnology(FADIB) Proceedings Vol. 23, 91-99(2017)
40. Kalu. O. Obasi, Mba T.C and P. C. Ogbonna (2018). Heavy metals concentration in
periwinkle (Littorina litterorea) harvested from Oron River, Akwa Ibom State and
Gberikoko River in Delta State, Nigeria. Research journal In Health
Sclences.www.lmsu.rjhs.com 2018
41. Kalu. O. Obasi, Jeremiah Joseph, P.C.Ogbonna and Chidozie Kanu ( 2018).Chemical
composition and microbial growth inhibition of Cassava effluent on Heterotrophic fungi
and bacteria. Research journal in Health Sciences.www.lmsu.rjhs.com. 2018.
42. Nwokocha, C.P, Obasi, K.O and Ogbonna P.C.F 2018). Environmental and Health Hazards
of Generator usage in Michael Okpara University of Agriculture, Umudike.Fed. Univ. Oye-
Ekiti(FUOYE) International Science Conference’ EARTH RESOURCES: paving the way
for wealth creation through scientific research.FAS.2018-SCI-058
43. Ogbonna P.C, Ukpai N and Obasi, K.O (2018). Assessment of metal contamination in
Ubeyi River and accumulation in fish and sediments Journal of Applied Sciences and
Environmental Management, University of Port
. www.uniport.edu.ng Harcourt.http://www.ajo!.info.info/stas/el8ce7d70f9ee99a6e01c29b75
8309e7baa3846d
44. 0gbonna, P.C, Nzegbule E.C, Obasi, K.O and Kanu, H (2018). Heavy metals in soil and
accumulation in medicinal plants at an industrial area in Enyimba city, Abia State, Nigeria.
Nigerian Journal of Environmental Sciences and Technology (NIJE$T),Vol 2 No 1, March
2018 pp xx-xx, www.nijest.com ISBN(print):2616-051X ISBN(electronic): 2616-0501.
45. Okereke, J.N, Udebuani, A.C, Ukaoma, A.A, Obasi, K.O, Ogidi, O.l and Onyekachi, U.C
(2016). Performance of Zea Mays on Soil Contaminated with Petroleum(oily) Sludge.
International Journal of Innovative and Advanced Studies (IJIRAS), Vo! 3 Issue 10, Sept
2016. ISSN 2394-4404
46. Chikezie Precious Chieze, Kalu .O. Obasi, Princewill .C. Ogbonna.(2019).Effects of
Selected Agro-Pesticides on the Pack Cell Volume and Total Leucocyte Count of Albino
Wistar Rats . International Journal of Environmental Health and Human Development.
47. Chikezie Precious Chieze, Kalu .O. Obasi, Princewill .C. Ogbonna.(2019).Effects of
Agro-Pesticides (basudyne and carbofuran) on the Liver Dysfunction Biomarkers of
Albino Wistar Rats. International Journal of Environmental Health and Human
Development.
48. Ogbonna P. C., Ukpai N. P., Obasi, K. O. and Umezuruike S. O(2020).
Appraising the Physico-chemical Characteristics and Heavy Metals in Pond Water at
Quarry Site in Ngwogwo, Ebonyi State, Nigeria.Nigerian Journal of Environmental
Sciences and Technology (NIJEST). www.nijest.com .ISSN (Print): 2734-259X | ISSN
(electronic): 2734-2603 .Vol 4, No. 2 October 2020, pp 237 – 252
49. Ogbonna, P.C., Ukpai, N.P., Obasi, K.O. and Umezuruike, S.O.(2020). Monitoring the
Distribution of Potentially Toxic Elements in Soil and Accumulation in Fodder and
Medicinal Plant Species at a Quarry site in Ebonyi State, Nigeria. Nigerian Research Journal
of Engineering and Environmental Sciences 5(2) 2020 pp. 535-553
50. Ikechukwu, Grant U, Obasi, Kalu O , Chikezie Precious C and Stephen Austin
C(2020).Antirancidity Effects of Crude Extracts of Citrus sineensis, Citrus limon and Citrus
aurantifolia Leaves on the Shelf Life of Palm Oil.1 st International Conference of the College
of Natural Resources and Environmental Management(CNREM), Michael Okpara University
of Agriculture, Umudike
51.Nwankwo, Olivia U and Obasi, Kalu O. (2020). Assessment of indoor micro-organisms,
CO 2, Humidity and Temperature in the dormitories of Demonstration Secondary School,
Michael Okpara University of Agriculture, Umudike, Abia State Nigeria. 1 st International
Conference of the College of Natural Resources and Environmental Management(CNREM),
Michael Okpara University of Agriculture, Umudike.
52. Kalu O. Obasi, Iwok Enimeno Sunday, A.C. Udebuani, J.N.Okereke (2020).
Assessment of: Benzene, Toluene Ethylbenzene, Xylene in Water and
Sediments from Itu, Ibeno and Ibaka River Estuary of Akwa Ibom State,
Nigeria.International Journal of Science and Research (IJSR).Volume 9 Issue 4, April 2020
www.ijsr.net.DOI: 10.21275/SR20417090522
53..Kalu. O. Obasi, Ogbonna, A. Onyekachi and Iwok Enimeno S(2020).Assessment of Polycyclic
Aromatic Hydrocarbons in Water, Sediments and Shellfish from Choba and Sama Rivers
of Rivers State, Nigeria.Journal of Environmental Science and Management. Kogi State
University
54 . Kalu. O. Obasi, Ogbonna, A. Onyekachi and Iwok Enimeno S(2020).Assessment of some nutrients
(NO 3 – ,N0 2 – ,NH 3 , PO 4 3- ) and sulphates (so 4 2- ,so 3 2- ) in Itu, Ibeno and Ibaka rivers of Akwa Ibom
State, Nigeria. Journal of Environmental Science and Management. Kogi State University
55. Obasi, K. O, Onwubiko, P. and Ogbonna, P. C (2019). Effects of Photographic Effluent
on Total Heterotrophic Bacteria and Fungi in Qua Iboe River, Ikwuano LGA, Abia State.
Journal of Environmental Health. The Journal of Environmental Health
(JEH) ISSN 0189-5885. https://sehon.org/publications/
56.*Nwoke-Ekpo, O.A. 1 , Obasi, K.O. 1 , Mpamah, I. C. 1 , Kanu, K.C( 2021).
A COMPARATIVE STUDY ON HEAVY METAL CONCENTRATION IN CRAB
(Callinectes amnicola) OBTAINED FROM IBENO, AKWA IBOM STATE, AKPABUYO
AND NSIDUNG, CROSS RIVER STATE. Journal of Environmental Health. The Journal
of Environmental Health
(JEH) ISSN 0189-5885. https://sehon.org/publications/
57. CHIKEZIE PRECIOUS CHIEZE, KALU .O. OBASI and PRINCEWILL C. OGBONNA.(2019).EFFECTS OF
AGRO-PESTICIDES (BASUDYNE AND CARBOFURAN) ON LIVER
DYSFUNCTION BIOMARKERS OF ALBINO WISTAR RATS. International Journal of Environmental Health
and Human Development( IJEHHD)
58. CHIKEZIE PRECIOUS CHIEZE, KALU O. OBASI and PRINCEWILL C. OGBONNA.(2019).EFFECTS
OF SELECTED AGRO-PESTICIDES ON THE PACKED CELL VOLUME AND TOTAL LEUCOCYTE COUNT
OF ALBINO WISTAR RATS. International Journal of Environmental Health and Human Development
(IJEHHD)
59. Ikechukwu Grant U, Kalu .O. Obasi, Chikezie Precious C, Stephen Austin .C.
(2022).ANTIRANCIDITY EFFECTS OF CRUDE EXTRACTS OF CITRUS SPP (Citrus
sineensis, Citrus limon, Citrus aurantifolia) LEAVES ON THE SHELF LIFE OF PALM OIL.
The Journal of Environmental Health
(JEH) ISSN 0189-5885. https://sehon.org/publications/
60. Mpamah I. C*, Kalu O. Obasi., Kanu, C., Ogbonna O. A. (2021). BIOACCUMULATION OF
HEAVY METALS IN SHELLFISH FROM SELECTED RIVERS OF RIVERS STATE,
NIGERIA. The Journal of Environmental Health
(JEH) ISSN 0189-5885. https://sehon.org/publications/