Lot 60799 – 1/2d green, specialised study of the T22, U22 and U23

1/2d green, specialised study of the T22, U22 and U23 control blocks neatly mounted and knowledgeably written up on 33 album pages, with 51 items including control strips of 3 and mostly blocks of six, with a few large including blocks of 12 and 20, showing a wonderful array of overprint, watermark and other control variations, an excellent basis for study and expansion.