21
by Koh, Hans, 1891-1971
Published 1957
22
by Krieger, Leonard
Published 1957
23
by Harrison, Selig S.
Published 1979
24
by Hugh-Jones, Stephen, 1945-
Published 1967
25
by Hodgkin, Thomas Lionel, 1910-
Published 1957
26
by Chavan, R. S.
Published 1973
27
by Johnson, Chalmers A.
Published 1962
28
by Nuseibeh, Hazem Zaki
Published 1956