Hooft van Huijsduijnen R (January 1998). "ADAM 20 and 21; two novel human testis-specific membrane metalloproteases with similarity to fertilin-alpha". Gene. 206 (2): 273–82. doi:10.1016/s0378-1119(97)00597-0. PMID9469942.
Hooft van Huijsduijnen R (January 1998). "ADAM 20 and 21; two novel human testis-specific membrane metalloproteases with similarity to fertilin-alpha". Gene. 206 (2): 273–82. doi:10.1016/s0378-1119(97)00597-0. PMID9469942.