Hatzler, F E
Pedoman praktis pramuniaga toko
Bhratara, 1973
Buku Teks
Hartzler, FE
Pedoman praktis menjual barang dan jasa = retail salesmanship/ FE. Hartzler
hratara KArya Aksara, 1982
Buku Teks
Smith, Genevieve Love
Medical terminology: a programmed text
Delmar Publishers, 1991
Buku Teks
Cox, Dennis P.
Introductory geology : a programmed text
W. H. Freeman, 1965
Buku Teks
Davis, Thomas A.
Analytic geometry a programmed text
McGraw-Hill, 1967
Buku Teks