Stuifbergen, N. H. (1980). Intersection of hyperbolae on the earth. Dept. of Surveying Engineering, University of New Brunswick.
Chicago-viite (17. p.)Stuifbergen, Nicholas H.J. Intersection of Hyperbolae on the Earth. Frederiction: Dept. of Surveying Engineering, University of New Brunswick, 1980.
MLA-viite (9. p.)Stuifbergen, Nicholas H.J. Intersection of Hyperbolae on the Earth. Dept. of Surveying Engineering, University of New Brunswick, 1980.
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