%0 Generic %T Compilation of the 50 direct primary systems. %U https://ezaccess.libraries.psu.edu/login?url=https://www.heinonline.org/HOL/Page?handle=hein.beal/cmplprys0001&id=1&size=2&collection=beal&index=alpha/C_beal %U https://ezaccess.libraries.psu.edu/login?url=https://www.heinonline.org/HOL/Page?handle=hein.beal/cmplprys0001&id=1&size=2&collection=scsl&index=alpha/C_scslbooks %7 Fourth edition.