by W.K. LEONARD
Year of Publication 03.04.2002

by A.E. SEAVER,W.K. LEONARD
Year of Publication 28.06.2006

by W.K. LEONARD, A.E. SEAVER
Year of Publication 28.07.2004

by W.K. LEONARD, D.W. LEONARD, B.D. SHALLES
Year of Publication 26.05.2004

by W.K. LEONARD, C.R. KESSEL, K.C. MELANCON
Year of Publication 11.09.2002

by Leonard, W.K. (Challow Products Agricultural Ltd, Faringdon (UK))
Year of Publication 1984

by Eschenbruch, R, Mora, S.J. de, Knowles, S.J, Leonard, W.K, Forrester, T, Spedding, D.J
Published in Vitis (01.03.1986)