I am looking for early sources (references) to the analysis in electrostatics where the polarization vector is rewritten in terms of bound charges and a surface polarization charge.
In terms of what I have already found, the answer is nothing. All standard recent texts such as Griffiths just give a derivation without sources. The paper by Joan Bromberg (1968) DOI:10.1119/1.1974442 reasons that Maxwell himself did not do the surface and bound charges analysis, and an early textbook by N.R. Campbell (1913) Modern Electrical Theory does not show it. My guess is that it appeared some time after 1913, but I may be wrong