8Hiratsuka S, Zhang S-L,and Nakagawa E et al. Selective inhibition of the growth of incompatible pollen tubes by S-protein in Japanese pear. Sex Plant Reprod, 2001;13: 209
9Ishimizu T, Sato Y, and Saito T et al. Identification and partial amino acid sequences of seven S-RNases associated with self-incompatibility of Japanese pear, Pyrus pyrifolia Nakai. J Biochem. 1996;120: 326