Suter, C. M.; Green, Frank O. (1 December 1937). "Phenoxthin. II. Extension of the Ferrario Reaction". Journal of the American Chemical Society. 59 (12): 2578–2580. doi:10.1021/ja01291a030.
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[۱], "Verfahren zur Darstellung von Phenoxthin und dessen Derivaten"