HARWOOD, F. COURTNEY. (1957). «MODERN DETERGENTS»Journal of the Royal Society of Arts 105 (5003): 467–484. ISSN0035-9114. (Noiz kontsultatua: 2021-06-23).
HARWOOD, F. COURTNEY. (1957). «MODERN DETERGENTS»Journal of the Royal Society of Arts 105 (5003): 467–484. ISSN0035-9114. (Noiz kontsultatua: 2021-06-23).