Langdon-Davies, J. (1951). NPL: Jubilee book of the National Physical Laboratory. H.M. Stationery Off..
Čikaški stil citiranja (17. izdanje)Langdon-Davies, John. NPL: Jubilee Book of the National Physical Laboratory. London,: H.M. Stationery Off., 1951.
MLA način citiranja (8. izdanje)Langdon-Davies, John. NPL: Jubilee Book of the National Physical Laboratory. H.M. Stationery Off., 1951.
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