1. 21. Massee A. M. Ann. Rept. East Malling Res. Stn. 1926 (Supplement II), p. 152, 1927.
2. 20. Massee A. M. Ann. Rept. East Malling Res. Stn. 1925 (General), pp. 76–80, 1 pl., 1925.
3. 25. Hatton R. G. & Amos J. Kent Cherry and Soft Fruit Catalogue, 07 1926.