liao abc

Does anybody have the original paper by Liao?

ZP Liao, HL Wong, BP Yang, YF Yuan, A transmitting boundary for transient wave analyses, Scientia Sinica (Series A), vol. XXVII, pp. 1063-1076, 1984

I've found it here (1984a.pdf)

http://liaozp.iem.cn/liaoPDF1/