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Eyeler, William (July 2001). "The changing assessments of John Snow's and William Farr's Cholera Studies". Sozial- und Präventivmedizin (İngilizce). 46 (4): 225-32. doi:10.1007/BF01593177. PMID11582849.
Eyeler, William (July 2001). "The changing assessments of John Snow's and William Farr's Cholera Studies". Sozial- und Präventivmedizin (İngilizce). 46 (4): 225-32. doi:10.1007/BF01593177. PMID11582849.