Cheng, H.H.ChengWu, TtTtWuTSUNG-TSONG WU2020-04-282020-04-2819710370-2693https://scholars.lib.ntu.edu.tw/handle/123456789/487162Considerations on Measuring Gamma + Gamma -] Pi+ + Pi- with Colliding Beamsjournal article10.1016/0370-2693(71)90078-5WOS:A1971K339600022