Mark Twain-Howells letters ; the correspondence of Samuel L. Clemens and William D. Howells, 1872-1910 /
edited by Henry Nash Smith and William M. Gibson with the assistance of Frederick Anderson.
- Cambridge, Belknap Press of Harvard University Press, 1960.
- 2 v. (xxv, 948 p.) illus., ports., facsims., geneal. tables. 25 cm.
Bibliographical references included in ''Note on editorial practice'' (v.1, p. xxi-xxv) ''Calendar of letters'': v.2, p. 883-903. ''Index of works by Samuel L. Clemens and William D. Howells'': v.2, p. 943-948.