1982, Aitutaki. 21st birthday of Princess Diana. Collective, progressive proof (9 phases) for the complete set (3 values), the souvenir sheet (contains the stamps of the set) and the layout of the miniature sheet. Printed together on one sheet each. Some printer's notes. MNH. Some slight paper wrinkles. In all 27 proof stamps, 9 proof souvenir sheets and 9 proof miniature sheets. UNIQUE.