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LibreCat: https://research-explorer.ista.ac.at/record/10899
DOI: 10.1016/b978-0-12-384719-5.00031-9

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LibreCat: https://research-explorer.ista.ac.at/record/3666
DOI: 10.1111/j.1095-8312.1983.tb00776.x