Parichart Sithisarn. (1993) Chemical modification on Bacillus penicillin acylase. Mahidol University,:ม.ป.ท.Parichart Sithisarn. 1993. Chemical modification on Bacillus penicillin acylase. ม.ป.ท.:Mahidol University,;Parichart Sithisarn. Chemical modification on Bacillus penicillin acylase. ม.ป.ท.:Mahidol University, 1993. Print.