Blokhuis, W. A. (1993). Vertisols in the central clay plain of the Sudan. s.n..
Chicagoスタイル(17版)引用形式Blokhuis, W. A. Vertisols in the Central Clay Plain of the Sudan. [Netherlands?: s.n., 1993.
MLA(8版)引用形式Blokhuis, W. A. Vertisols in the Central Clay Plain of the Sudan. s.n., 1993.
警告: この引用は必ずしも正確ではありません.