Orchids of Peru / Charles Schweinfurth.

v.30:no.2(1959)

Flora of Guatemala / Paul C. Standley and Louis O. Williams.

v.24:pt.9:no.3-4(1973)

Flora of Guatemala / Paul C. Standley and Louis O. Williams.

v.24:pt.7:no.1(1961)

Monograph of the genus Russelia (Scrophulariaceae)

v.29:no.4(1957)

Tropical American plants, X / Louis O. Williams.

v.32:no.4(1968)

Tropical American plants, XI / Louis O. Williams.

v.32:no.12(1970)

Contributions to the flora of Venezuela : from Ericaceae through Compositae / Julian A. Steyermark and collaborators.

v.28:no.3(1953)

Flora Costaricensis / William Burger, editor.

v.40(1977)

Flora of Guatemala / Dorothy L. Nash, Louis O. Williams ; genera contributed by Kenneth M. Becker ... [et al.].

v.24:pt.12(1976)

Flora of Guatemala / Paul C. Standley and Louis O. Williams.

v.24:pt.7:no.4(1963)

Contributions to the flora of Venezuela / [Julian A. Steyermark and collaborators].

v.28:no.1(1951)

New species in the palm genus Syagrus Mart., II / [by] S.F. Glassman.

v.31:no.13(1968)

Revision of the genus Vascellum (Lycoperdaceae).

v.32:no.9(1970)

Tropical American plants, VII / Louis O. Williams.

v.31:no.6(1965)

Agriculture, Tehuacan Valley.

v.31:no.3(1965)