Langat, Penina Chepkorir; Cheruiyot, Peter Kimutai; Naibei, Isaac Kiprotich; Rop, Willitter Chepkemoi(International Journal of Scientific and Research Publications, 2019-11)
Kemboi, Raymond Kipyegon; Naibei, Isaac Kiprotich; Sirmah, Peter Kipkosgei; Cheruiyot, Peter Kimutai(International Journal of Engineering and Management Research, 2019-08)