3 1 20 William L. Stephens Primary Author Blackhurst Primary Author Magliocca Primary Author mixed material 0471024791 Canada John Wiley &Sons, Inc. 1982 Jack L. Smith Additional Author Robert M. Keith Additional Author William L. Stephens Additional Author mixed material 007059127X USA McGraw-Hill 1986 Jack L. Smith Additional Author Robert M. Keith Additional Author William L. Stephens Additional Author mixed material 0070591202 United States of America McGraw-Hill Book Company 1986