I reluctantly consult a copy of the 4th edition (a recent one, though not the latest) of the boring MLA Handbook for Writers of Research Papers. In §4.2 "MLA style" (pp 104-5), it tells us that MLA style is to use inline citations such as "(Marcuse 197)", adding a bibliography in which the reader may see that "Marcuse" is Sibyl Marcuse's book A Survey of Musical Instruments and necessary publication info. But look, I've no more wish to dwell on what this or that particular MoS says than you do, and I'll stick that book back on its shelf where it may deservedly gather more dust. I've never thought nor intentionally suggested that the article should specify the precise location of the authority for each of its assertions. Saying that the entire content of the article (now that I've deleted the speculative gay trivia) comes from one or other of those two books would be a big start. In fact I'll do it right now. Then the pastel box can be deleted, though I suppose the article should eventually give the precise location of each quotation.