8Ian Stewart, "Tales of a Neglected Number", Scientific American Inc. 1996, T. 274, No. 6. C. 102~103. http:// members, fortunecity, com/templarser/padovan, html.
9Richard Paduvan, "Dom Hans Van Der Laan and the Plastic Number", pp. 181- 193 in Nexus IV. Architecture and Mathematics, eds. Kim Williams and Jose Francisco Ro- drigues, Fucecchio (Florence) : Kim williams Books, 2002.
