NIUE, 1920, 6p Deep Green & Red Brown, Inverted Center (39a).
Single with top right sheet corner selvage, Fine, also incl. Penrhyn Island 1p Red and Black Inverted Center No. 26a with a horizontal crease, otherwise Very Fine, Gibbons does not list these two varieties because, according to footnotes, these "were never supplied to the post office"
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