- "Godel, Escher, Bach" by Douglas Hofstadter - "Foucalt's pendulum" by Umberto Eco. - "A Perfect Vacuum" by Stanislaw Lem. - "Hitchhiker's Guide to the Galaxy"

- "Godel, Escher, Bach" by Douglas Hofstadter - "Foucalt's pendulum" by Umberto Eco. - "A Perfect Vacuum" by Stanislaw Lem. - "Hitchhiker's Guide to the Galaxy" by Douglas Adams.