Unesco. (1971). The surveillance and prediction of volcanic activity: A review of methods and techniques. Unesco.
Chicago-referens (17:e uppl.)Unesco. The Surveillance and Prediction of Volcanic Activity: A Review of Methods and Techniques. Paris: Unesco, 1971.
MLA-referens (9:e uppl.)Unesco. The Surveillance and Prediction of Volcanic Activity: A Review of Methods and Techniques. Unesco, 1971.
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