Harry Adam Knight is a joint pseudonym of Leroy Kettle & John Brosnan.

Leroy Richard Arthur "Roy" Kettle OBE (born 1949) is a retired United Kingdom civil servant. Science fiction fans know Kettle as a prolific co-author with John Brosnan, publishing under the names Harry Adam Knight and Simon Ian Childer.
Source: Wikipedia
May 21, 1992
Cover of Bedlam

Bedlam

May 1, 1990
Cover of Death Spore

Death Spore

Mar 21, 1985
Cover of The Fungus

The Fungus

Jun 21, 1984
Cover of Carnosaur

Carnosaur

Sep 15, 1983
Cover of Slimer

Slimer