INCLUSIVE MUON PRODUCTION AT CM ENERGIES 12 TO 31.6 GEV - Berger C; Genzel H; Grigull R; Lackas W; Raupach F; Klovning A; Lillestöl E; Lillethum E; Skard J; Ackermann H; Alexander G; Barreiro F; et al. (Physical Review Letters, 1980)