by Gregory, Cecil L
Year of Publication 1958

by Wilkening, Eugene A, Gregory, Cecil L
Year of Publication 1941

by Gregory, Cecil L, Lionberger, Herbert F. (Herbert Frederick)
Year of Publication 1968

by Lively, C. E. (Charles Elson), Gregory, Cecil L
Year of Publication 1948

by Lively, C. E. (Charles Elson), Gregory, Cecil L
Year of Publication 1939

by Ikerd, John E, Gregory, Cecil L, Cramer, Charles L. (Charles Leonard)
Year of Publication 1971

by Gregory, Cecil L, Grinstead, Mary Jo (Mary Josephine), Wade, Jerry L. (Jerry Lee)
Year of Publication 1969

by Lionberger, Herbert F. (Herbert Frederick), Gregory, Cecil L, Chang, Hsi Chih
Year of Publication 1967