المؤلفون: JACKSON, ROBERT H., RÖSBERG, CARL G.
Original Material: Edition: 1328 p.
الإتاحة: https://www.jstor.org/stable/jj.8085287
المؤلفون: COLEMAN, JAMES S., ROSBERG, CARL G.
Original Material: Edition: 1746 p.
الإتاحة: https://www.jstor.org/stable/jj.2430694