Society for Psychical Research (Great Britain): Journal of the Society for Psychical Research. Society for Psychical Research., 2004 (google.com).
David R. Mandel, Denis J. Hilton, Patrizia Catellani: The Psychology of Counterfactual Thinking. Psychology Press, 2005, ISBN 978-0-415-32241-6, S.145 (google.com).
John Maltby, Liz Day, Ann Macaskill: Personality, Individual Differences and Intelligence. Prentice Hall, 2010, ISBN 978-0-273-72290-8, S.496 (google.com).
Laura Vanderkam: Grindhopping: Build a Rewarding Career Without Paying Your Dues. McGraw Hill Professional, 2006, ISBN 978-0-07-147933-2 (google.com).
Ken Robinson, Lou Aronica: The Element: How Finding Your Passion Changes Everything. Penguin Books Limited, 2009, ISBN 978-0-14-191125-0, S.41 (google.com).
Ben Sherwood: The Survivors Club: The secrets and science that could save your life. Penguin Books Limited, 2009, ISBN 978-0-14-104120-9, S.125 (google.com).
Peter Sims: Little Bets: How breakthrough ideas emerge from small discoveries. Random House, 2011, ISBN 978-1-4090-3803-0, S.121 (google.com).