• http://ir-library.ku.ac.ke/handle/123456789/1589
• http://ir-library.ku.ac.ke/handle/123456789/18496
• http://ir-library.ku.ac.ke/handle/123456789/18502
• http://ir-library.ku.ac.ke/handle/123456789/18509
• http://ir-library.ku.ac.ke/handle/123456789/18506
• http://ir-library.ku.ac.ke/handle/123456789/18513
• http://ir-library.ku.ac.ke/handle/123456789/18510