المؤلفون: Johnson, Melvin C.
Original Material: 240 p.
الإتاحة: https://www.jstor.org/stable/j.ctt4cgp7m
المؤلفون: Bringhurst, Newell G., Edited by
Original Material: 192 p.
الإتاحة: https://www.jstor.org/stable/j.ctt46nwv5