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2. 2) O. Keil, R. Mitsche, A. Legat and H. Trenker: Arch. f. Eisenhüttenwesens, 7 (1934), 579.
3. 3) C. Adey: Giesserei, 33–35 (1948), 67.
4. 4) M. Maruyama: 30th International Foundry Congress Paper (Prague 1963), 177.
5. 5) H. Morrogh and W. J. Williams: Paper No. 875 read before the Annum Meeting (1947) of the Inst. of British Foundrymen;