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Here is one: 

"For anyone who has read Eliot's poetry and wondered if they might have missed some of the references and layers of meaning (in other words, anyone who has ever read Eliot’s poetry), this volume is a godsend. The depth of research, drawing on Eliot’s letters, articles, audio recordings, and innumerable other sources, is breathtaking, and every page in the annotations includes some gems of interest or insight.

Two volumes have been published, but if you can only afford one, this book (Volume 1) is the one to get. It includes everything in Eliot’s own edition of the Collected Poems (including, of course, The Waste Land and Four Quartets), followed by uncollected poems intended for publication and an editorial composite of The Waste Land based on Eliot’s drafts. The second volume has the cat poems, Eliot’s translation of St-John Perse’s Anabase, and the informal and “improper” verse, such as Ode to a Roman Coot (a parody of Keats’s Ode to a Nightingale). Volume 2 also contains the textual history of the poems in both volumes, including variant readings from drafts and different printings (important, but more for the scholar than the casual reader).

The annotations in Volume 1 are printed in a separate 900-page “commentary” section which comprises the bulk of this massive book. Each annotation begins with the line number, followed by the phrase or line being commented on (printed in bold), then the notes, which may be a line or two of explication, a quote from another poem or book that Eliot is referencing, or even a small essay. The commentary is highly readable, and if you know the poems quite well already, it’s a lot of fun just to browse through it.

I have only begun to explore this book, but even in a short time it’s given me a new appreciation and enjoyment of Eliot’s verse. Highly recommended."