Life and letters of Sir Joseph Dalton Hooker, O.M., G.C.S.I. : based on materials collected and arranged by Lady Hooker /
London :J. Murray,1918.
University of California Libraries (archive.org)
Evidence reported by judyjordan for item lifelettersofsir01hookrich on April 17, 2007: no visible notice of copyright; stated date is 1918.