The complete set in detail
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B074
SG No. B88
1952 - Olympic games festival at Helsinki : Watermark 'multiple crosses and circles' - 4 Pfg. ; yellow-brown
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B075
SG No. B89
1952 - Olympic games festival at Helsinki : Watermark 'multiple crosses and circles' - 10 Pfg. ; green
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B076
SG No. B90
1952 - Olympic games festival at Helsinki : Watermark 'multiple crosses and circles' - 20 Pfg. ; red