6B. J. King,L. S. Lee,P. T. Scott.Identification of triploid Citrus by isozyme analysis[J]. Euphytica . 1996 (2)
7T. Visser.Juvenile phase and growth of apple and pear seedlings[J]. Euphytica . 1964 (2)
8Dr. G. J. Dowrick.Abnormal gametogenesis and embryo abortion in the pear variety beurré bedford (Pyrus communis)[J]. Zeitschrift für Vererbungslehre . 1958 (1)
9Richard L,Bell & Richard H.Zimmermman.Comblning Ability Analysis of Jurenile Perid in Pear. HortScience . 1990
10Mass J L.Pollen ultrastructure of strawberry and other small- fruit crops.J.Amer. he. Horticultural Science . 1977