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Jeffrey C. Lagarias, Colin L. Mallows, Allan R. Wilks (2002-04). “Beyond the Descartes Circle Theorem”. The American Mathematical Monthly109 (4): 338-361. doi:10.2307/2695498. JSTOR2695498.
jstor.org
Jeffrey C. Lagarias, Colin L. Mallows, Allan R. Wilks (2002-04). “Beyond the Descartes Circle Theorem”. The American Mathematical Monthly109 (4): 338-361. doi:10.2307/2695498. JSTOR2695498.