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4. A. Erdêlyi, W. Magnus, F. Oberhettinger & F. G. Tricomi, Higher Transcendental Functions, vol. 2, McGraw-Hill, New York, 1953, p. 62.
5. E. Jahnke, F. Emde & F. Lösch, Tables of Higher Functions, McGraw-Hill, New York, 1960. p. 229.