“Old Friends across Time” by Paul J. Nahin “‘Old Friends Across Time’” by Paul J. Nahin, Analog Science Fiction / Science Fact, May 1979.
The Invitation by Paul J. Nahin “The Invitation” by Paul J. Nahin, in The Fourth Omni Book of Science Fiction, edited by Ellen Datlow (Zebra Books, July 1985).
Twisters by Paul J. Nahin “Twisters” by Paul J. Nahin, Analog Science Fiction / Science Fact, May 1988.
Time Machines: Time Travel in Physics, Metaphysics and Science Fiction by Paul J. Nahin If you have only one reference book on your shelf—on any topic—this must be it. Get the second edition. This is, I believe, a book for the adventurous in spirit. Time Machines: Time Travel in Physics, Metaphysics and Science Fiction, Second Edition by Paul J. Nahin (Springer-Verlag, November 1998).