Right-click as needed:

Frank Adams, 1904 (British, 1871-1944)

Unk White (Australian, 1900-1986)

Ota Janeček, Czech artist, 1961

English artist-writer Barbara C. Freeman (1906-1999)

I came across these in Tumblr’s thoroughly wonderful “Vintage Illustration” stream:
https://www.tumblr.com/tagged/vintage illustration