Isaac Asimov
4 appearances across 4 restored issues — every one readable in full, free.
Astounding Science Fiction, June 1944 (British Edition) — 1944 “DEATH SENTENCE” · p.55 Read the full issue (68 pages) → 
Beyond Fantasy Fiction, September 1953 — 1953 “KID STUFF” · p.121 Read the full issue (164 pages) → 
Authentic Science Fiction Monthly No. 78 — 1957 “Me Wears Die Ward” (novelette) · p.72 Read the full issue (130 pages) → 
Authentic Science Fiction Monthly, No. 82 — 1957 “It's Such a Beautiful Day” (novelette) · p.104 Read the full issue (130 pages) → Appearances are extracted from each issue's own printed contents page; entries we can't read confidently are withheld rather than guessed.