The Knight novel has no publication date (n.d.) but is copyright 1965:
Click here to view all of the covers by Paul Lehr that I’ve posted to date.
Look Here: Two SF covers by Paul Lehr
"This day's experience, set in order, none of it left ragged or lying about, all of it gathered in like treasure and finished with, set aside." –Alice Munro, "What is Remembered"
Ragged Claws Network 
Nice! Never heard of The Asutra. Here in Brazil this blue alien is the cover of Asimov’s The Martian Way (http://www.skoob.com.br/livro/15286-n-s-os-marcianos)
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