Nonfiction:
Editor of:
Living Authors, 1931
Authors Today and Yesterday, 1933
Junior Book of Authors, 1934
British Authors of the Nineteenth Century, 1936
American Authors 1600-1900, 1938
Twentieth Century Authors, 1942; first supplement, 1955
British Authors Before 1800, 1952
Poems of John Keats, 1964
European Authors 1000-1900, 1967
The Essential Blake, 1987

Essays:

The Wild Braid: A Poet Reflects on a Century in the Garden, 2005( A collaboration with Genine Lentine)

Publications:
Contributor to :
Atlantic, New Republic, New Yorker, Antaeus, New York Review of Books, American Poetry Review, and Harper's

Translator: (with others)
Verse Antiworlds (A. Voznesensky), 1966
Antiworlds and the Fifth Ace, 1967
Stolen Apples (Y. Yevtushenko), 1971 (with Max Hayward)
Poems of Akhmatova, 1973
Story Under Full Sail (A. Voznesensky), 1974