by Guo, Y., Gong, Z.F., Mo, H.D., Wang, S.X., Yang, B.Z., Wu, T.J., Bian, Z.H., Tang, X.W., Xiong, C.S., Zhu, J.S., Xiao, J.Y., Shen, T.D., Quan, M.X., Wang, J.T.
Published in Physics letters. A (03.10.1994)

by Kuo, S.Z, Xiong, P.S, Bian, Z.H, Wu, W.Z, Sun, Y.M
Published in Chiang-su nung yeh k'o hseuh. Jiangsu nongye kexue = Jiangsu agricultural science (1982)