Sheikh และ Shafqat Jawaid. (1999) Knowledge, attitude and practice of the sanitary workers towards management of hospital waste in Islamabad, Pakistan. Mahidol University,:ม.ป.ท.Sheikh และ Shafqat Jawaid. 1999. Knowledge, attitude and practice of the sanitary workers towards management of hospital waste in Islamabad, Pakistan. ม.ป.ท.:Mahidol University,;Sheikh และ Shafqat Jawaid. Knowledge, attitude and practice of the sanitary workers towards management of hospital waste in Islamabad, Pakistan. ม.ป.ท.:Mahidol University, 1999. Print.