Papua New Guinea, Geological Survey of Papua New Guinea, & George, J. E. (1978). Hydrogeological investigations 1977. Office of Minerals and Energy.
Chicago-viite (17. p.)Papua New Guinea, Geological Survey of Papua New Guinea, ja J. E. George. Hydrogeological Investigations 1977. [Port Moresby]: Office of Minerals and Energy, 1978.
MLA-viite (9. p.)Papua New Guinea, et al. Hydrogeological Investigations 1977. Office of Minerals and Energy, 1978.
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