*Pacey, Arnold, (1974, 2ed 1994),The Maze of Ingenuity The MIT Press, Cambridge, Mass, 1974, 1994, cited here*Singer, C., Holmyard, E.J., Hall, A. R and Williams, T. I.
*Pacey, Arnold, (1974, 2ed 1994),The Maze of Ingenuity, The MIT Press, Cambridge, Mass, 1974, 1994, cited here*Singer, C., Holmyard, E.J., Hall, A. R and Williams, T. I.