Norman, D. W. (1973). Economic analysis of agricultural production and labour utilisation among the Hausa in the North of Nigeria. Dept. of Agricultural Economics.
Chicago-viite (17. p.)Norman, D. W. Economic Analysis of Agricultural Production and Labour Utilisation Among the Hausa in the North of Nigeria. [East Lansing: Dept. of Agricultural Economics, 1973.
MLA-viite (9. p.)Norman, D. W. Economic Analysis of Agricultural Production and Labour Utilisation Among the Hausa in the North of Nigeria. Dept. of Agricultural Economics, 1973.
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