One of the aspects of the footnotes of The Letters of Sylvia Plath that I most enjoyed was cross-referencing to letters to which Plath responded. There are very few instances where we have both sides of the letters--the most complete being the letters between Plath and Gordon Lameyer and Plath to Lynne Lawner. Periodically, Richard Norton and Eddie Cohen, to name but two, would quote Plath's words back to her in her letters which was always illuminating. Particularly as these original letters no longer appear to be extant.
My intention in doing this work in the footnotes was to help readers in pinpointing those letters to Plath in an archive; to save them time, perhaps. But overall, just to try to get anything relevant to the letter on the page. You will see them each at the bottom of the page, usually formatted the same in the attempt to be both consistent and predictable. For example,
"See Richard Norton to SP, 3 March 1953; held by Lilly Library."
"See Lynne Lawner to SP, 7 December 1958 and 21 January 1959; held by Lilly Library."
"See Alan Ross to SP, 12 October 1960; held by Smith College."
The rest is up to you if you want to see the correspondence Plath received.
Another aspect of trying to add value to the Letters, which I fear was done less consistently and comprehensively than ought to have been done, were cross-references to episodes or content that appear in Plath's journals. I can make excuses for the layers and levels of complexity that went into the construction and production to Plath's Letters but I do not believe anyone wants to read any moaning. (However, if anyone does want to know about it...) But, be that as it may, there are some cross-references to the Journals. For example,
"According to SP's journal, she mailed 'The Trouble-Making Mother' to the Saturday Evening Post by 25 July. Journals of Sylvia Plath: 290."
"The idea for 'Changeabout in Mrs Cherry's Kitchen' appeared in SP's journals on 4 January 1958; Journals of Sylvia Plath: 304. Published as 'Mrs. Cherry's Kitchen' in Sylvia Plath, Collected Children’s Stories (London: Faber & Faber, 2001)."
I hope this is helpful!
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