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The Development of transportation in modern England : Jackman, W[illiam] T. ; With a new introd. by W. H. Chaloner
Jackman, William T., (1962)
Congo, République Centraafricaine, Gabon, Tchad : Agence Trans Equatoriale des Communications
(1961)
Traffic and transport in Nigeria : the example of an underdeveloped tropical territory
Walker, Gilbert, (1959)