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Journal of physics. A. Mathematical and general
ZB; Vol. 8. 1975 - Vol. 37. 2004
IKP; Vol. 8. 1975 - Vol. 9. 1976
ZB; Vol. 8. 1975 - Vol. 37. 2004
IKP; Vol. 8. 1975 - Vol. 9. 1976
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