Eckholm, Erik P.
Losing ground : environmental stress and world food prospects
W.W. Norton, 1976
Buku Teks SO
Reaching for the skies
Academy Group, 1995
Buku Referensi
Reaching for the skies
edited by Toy Magie
Academy Editions, 1995
Buku Teks SO
Tymieniecka, Anna-Teresa
Art, literature, and passions of the skies
Springer, 2012
eBooks
Fish, Donald
Lawless skies the fight against international air crime
G.P. Putnam's Sons , 1962
Buku Teks