Still further examples of anionic surfactants include fatty acids (of formula R???COO???M+, where R is an organic radical and M+ is a counter-cation), for example, a dodecanoic acid sodium salt, or other acids including phosphoric acids, cholic acids, fluoro-organic acids such as lithium-3-[2-(perfluoroalkyl)ethylthio]propionate, or mixtures thereof.