Egon and Eduardo visit the New York City Public Library to research Antonio Garibaldi and Luko. They look through "Principia Mathematica." This a title of an early 20th century three volume treatise on mathematical logic and philosophy by Alfred North Whitehead and Bertrand Russell.
Kylie studies I-Ching, one of China's oldest texts, and references its use in stock trade.
On Roland's night stand is a framed photograph of himself with his little brother Casey, who will appear in Grundelesque (1997).