Cook Islands (Aitutaki)

1982 Birth of Prince William, IMPERFORATE Set of 3

Single from top left of the sheet

On white gummed paper, Mint Never Hinged

Scott 268-70, $5.60 for a normal set of 3, Plate Proofs or Imperforate are not listed

Stanley Gibbons Catalogue: #415, 417 & 419, Plate Proofs or Imperforate are not listed

I believe these to be Plate Proofs. The printer of this stamp issue Fournier S.A sold its philatelic archives of stamp artwork and proofs in 2007 through the German stamp dealer and auction house Gärtner.