Mogollon, R. (1980). ON A CLASS OF CONTINUOUS FLOW. International Journal of Mathematics and Mathematical Sciences, 1980(), 267-274. https://doi.org/10.1155/S0161171280000191
W. V. O. Quine(1973)。On What is there?。哲學論集,(2),29-51。https://doi.org/10.29699/FJPS.197306.0006