Birch, P. (1975). Thirty games a week: A study of the use of artificial grass pitches in Islington and Hackney. Sports Council.
Chicago-viite (17. p.)Birch, P. Thirty Games a Week: A Study of the Use of Artificial Grass Pitches in Islington and Hackney. London: Sports Council, 1975.
MLA-viite (8. p.)Birch, P. Thirty Games a Week: A Study of the Use of Artificial Grass Pitches in Islington and Hackney. Sports Council, 1975.
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