1) Irvine, Susan, 1928-, Garden of a Thousand Roses (LC|n 94057277)
2) Susan Irvine, Laura Ashley bedrooms, freelance journalist; also worked at Vogue
3) Irvine, Susan (Susan Elizabeth), The Old English Boethius, Eng. Language and Lit. at University College, London (LC|n 2002022002)
4) I think the author of Muse and Corpus is probably actually the same as the author of Laura Ashley bedrooms, given that they're both described as journalists with stuff related to Vogue.