@article{aup:/content/journals/10.5117/TVGESCH2013.2.B22, author = "Theunissen, Bert", title = "Obe Postma in verschillende gedaanten - Jan Guichelaar, George B. Huitema, Hylke de Jong ed., Zekerheden in waarnemingen. Natuurwetenschappelijke ontwikkelingen in Nederland rond 1900 (Verloren; Hilversum 2012) 237 p., ill., €17,95 ISBN 9789087041946", journal= "Tijdschrift voor Geschiedenis", year = "2013", volume = "126", number = "2", pages = "283-284", doi = "https://doi.org/10.5117/TVGESCH2013.2.B22", url = "https://www.aup-online.com/content/journals/10.5117/TVGESCH2013.2.B22", publisher = "Amsterdam University Press", issn = "2352-1163", type = "Journal Article", }