Muhammad Ashraf; Muhammad Yousaf; Z.I. Ahmad; Amir Aman ullah(Faisalabad: Institute of Soil & Environmental Sciences University of Agriculture, Faisalabad. Pakistan, 2002-01-08)
Muhammad Ashraf; Safdar Ali; Ijaz-ut-Hassa(Faisalabad: Institute of Soil & Environmental Sciences University of Agriculture, Faisalabad. Pakistan, 2002-01-08)