This user subpage is currently inactive and is retained for historical reference. If you want to revive discussion regarding the subject, you might try contacting the user in question or seeking broader input via a forum such as the village pump. I seldom see this bug any more, so it must have been fixed in almost all cases. Each example below (but not the counterexample section) used to have a double period as seen here, but today I see it only in the "Aspinall" example.

Duplicate period examples and counterexamples

The double period bug occurs because Category:Citation templates such as Template:Cite web and Template:Cite book, but for some reason not Template:Citation itself, add periods after many of their parameters. If that parameter has wrongly been ended with a period, usually because of an abbreviation, then the template may add a duplicate period. At present about 45,000 Wikipedia articles have this problem, placing it among Wikipedia's most frequent typos. There's more analysis at Template talk:Cite web/Archive 6#Double period bug.

Search for ".." to make the examples stand out. For instance, the first reference ends with duplicate periods, and the second has duplicate periods after "1890". For some obscure reason, a few examples that look like ".." can't be found by searching for "..". I have so many examples to help my WP:AWB software learn to distinguish when to remove a period and when to leave it alone; AWB reads the code you can see on the edit page, not what you see here.

Examples

• Harris, N. (2006). The Foreign Revolution. How Overseas Footballers Changed the English Game. London: Aurum Press Ltd.
• Ramsden, J. (2006). Don't Mention the War. The British and the Germans since 1890. London: Little, Brown Book Group.
• Foster, Kathleen A. "Thomas Eakins - Scenes from a Modern Life: Biography 1886: Indicted by Rumor". PBS. Retrieved January 6, 2008.
• Edney, Matthew H. "The Cartographic Creation of New England". Osher Map Library and Smith Center for Cartographic Education, University of Southern Maine. Retrieved 2007-05-03.
• Chartier, Charles S. "Livestock in Plymouth Colony". Plymouth Archaeological Rediscovery Project. Retrieved 2007-05-03.
• "Boortz Bio". Cox Radio Interactive & Cox Radio, Inc. 2007. Retrieved 2007-05-18.
• "Jack M. Whiteside, P.E." Barnes and Click Inc. 2007. Retrieved 2007-05-18.
• "The Top Talk Radio Audiences". Focus Communications, Inc. 2007. Retrieved 2007-05-18.
• "Imagination is Fun by Gregg Calkins". F.A.N.A.C. Inc. Retrieved 23 December 2007.
• "Westercon 55 Progress Report 2" (PDF). Los Angeles Science Fantasy Society, Inc. Retrieved 23 December 2007.
• Ashley, Michael (1976). The History of the Science Fiction Magazine Vol. 3 1946–1955. Chicago: Contemporary Books, Inc. ISBN 0-8092-7842-1.
• Atheling, Jr., William (1974). More Issues at Hand. Chicago: Advent: Publishers, Inc. ISBN 0-911682-18-X.
• Malcolm Edwards and Peter Nicholls, "Astounding Science-Fiction", in Clute, John (1993). The Encyclopedia of Science Fiction. New York: St. Martin's Press, Inc. p. 62. ISBN 0-312-09618-6. ((cite book)): Unknown parameter |coauthors= ignored (|author= suggested) (help)
• Malcolm Edwards and Peter Nicholls, "SF Magazines", in Clute, John (1993). The Encyclopedia of Science Fiction. New York: St. Martin's Press, Inc. p. 1066. ISBN 0-312-09618-6. ((cite book)): Unknown parameter |coauthors= ignored (|author= suggested) (help)
• Brian Stableford, "Imagination", in Clute, John (1993). The Encyclopedia of Science Fiction. New York: St. Martin's Press, Inc. p. 615. ISBN 0-312-09618-6. ((cite book)): Unknown parameter |coauthors= ignored (|author= suggested) (help)
• Peter Nicholls and John Clute, "Genre SF", in Clute, John (1993). The Encyclopedia of Science Fiction. New York: St. Martin's Press, Inc. p. 483. ISBN 0-312-09618-6. ((cite book)): Unknown parameter |coauthors= ignored (|author= suggested) (help)
• Brian Stableford, "Amazing Stories", in Clute, John (1993). The Encyclopedia of Science Fiction. New York: St. Martin's Press, Inc. p. 25. ISBN 0-312-09618-6. ((cite book)): Unknown parameter |coauthors= ignored (|author= suggested) (help)
• Tuck, Donald H. (1982). The Encyclopedia of Science Fiction and Fantasy: Volume 3. Chicago: Advent: Publishers, Inc. ISBN 0-911682-26-0.
• "100 best companies for working mothers 2004". Working Mother Media, Inc. Archived from the original on 2004-10-17.
• "Caterpillar Brings Engines with ACERT Technology to Off-Road Machines". Caterpillar Inc. Retrieved 2007-08-05.
• Bongianni, Maurizio (editor) (1988). Simon & Schuster's Guide to Horses and Ponies. New York, NY: Simon & Schuster, Inc. ISBN 0671660683. ((cite book)): |author= has generic name (help)
• "Responsibility for the Terrorist Atrocities in the United States, 11 September 2001". 10 Downing Street, Office of the Prime Minister of the U.K. November 2001. Retrieved 2006-09-29.((cite web)): CS1 maint: date and year (link)
• Gordon, Joseph S. (1988). "East German psychological operations: a 1965 case study". In Gordon, Joseph S. (ed.). Psychological operations: the Soviet challenge. Boulder, CO: Westview Press. ISBN 9780813373959.
• Baker, Frederick (2004). "The Berlin Wall". In Ganster, Paul; Lorey, David E. (eds.). Borders and border politics in a globalizing world. Lanham, MD: Rowman & Littlefield. ISBN 9780842051040.
• "Encyclopedias and Dictionaries". Encyclopædia Britannica, 15th ed. Vol. 18. Encyclopædia Britannica. 2007. pp. 257–286.
• Aspinall, Robert W.. Teachers' Unions and the Politics of Education in Japan. State University of New York Press; 2001. ISBN 0-7914-5050-3.
• Fuller, R. Buckminster (1963). [[Operating Manual for Spaceship Earth]] (First ed.). New York: E.P. Dutton & Co. ISBN 0-525-47433-1. Retrieved 2007-04-21. ((cite book)): URL–wikilink conflict (help)
• Meissner, Carl (1856). "Proteaceae". In de Candolle, A. P. (ed.). Prodromus systematis naturalis regni vegetabilis. Vol. 14. Paris: Sumptibus Sociorum Treuttel et Wurtz.
• Duggan, Charles (1965). "From the Conquest to the Death of John". In Lawrence, C. H. (ed.). The English Church and the Papacy in the Middle Ages (1999 reprint ed.). Stroud: Sutton Publishing. pp. 63–116. ISBN 0-7509-1947-7.
• Cheng MS, Ferkel RD, Applegate GR (1995). "Osteochondral lesion of the talus: A radiologic and surgical comparison" (Document). New Orleans, LA. ((cite document)): Cite document requires |publisher= (help)CS1 maint: multiple names: authors list (link) Paper presented at Annual Meeting of the Academy of Orthopaedic Surgeons.

Counterexamples

• Wright, E.L. (9 May 2009). "What is the evidence for the Big Bang?". Frequently Asked Questions in Cosmology. UCLA, Division of Astronomy and Astrophysics. Retrieved 2009-10-16.
• "Apple Reports First Quarter Results" (Press release). Apple Inc. January 21, 2009. Retrieved 2009-04-06.
• Glut, Donald F. (1982). The New Dinosaur Dictionary. Secaucus, NJ: Citadel Press. p. 280. ISBN 0-8065-0782-9.
• Callison, George (1984). "Tiny dinosaurs: are they fully grown?". Journal of Vertebrate Paleontology. 3 (4): 200–209. doi:10.1080/02724634.1984.10011975. ((cite journal)): Unknown parameter |coauthors= ignored (|author= suggested) (help)
• Steffensmeier, D.J. (1986). The Fence: In the Shadow of Two Worlds. Rowman and Littlefield Publishers. p. 60.
• Kay, K. (2000). Male Lust: Pleasure, Power, and Transformation. Haworth Press. p. 103. ISBN 1560239824. ((cite book)): Unknown parameter |coauthors= ignored (|author= suggested) (help)
• Crego, Carl R. (2004). Fort Ticonderoga. Charleston, South Carolina: Arcadia Publishing. ISBN 9780738535029. OCLC 56032864.
• Afable, Patricia O. (1996). "Place Names". In Goddard, Ives, ed (ed.). Languages. Handbook of North American Indians, Volume 17. Washington, DC: Smithsonian Institution. ISBN 9780160487743. OCLC 43957746. ((cite book)): |editor-first= has generic name (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)CS1 maint: multiple names: editors list (link)
• Blackburn B, Brennan N, and Leber K (2003). "In situ Scuba Diver Identification of Hatchery Released Red Snapper, Lutjanus campechanus, Using Visual Implant Elastomer Tags in the Gulf of Mexico". In: SF Norton (Ed). Diving for Science...2003. Proceedings of the American Academy of Underwater Sciences (22nd annual Scientific Diving Symposium). Retrieved 2008-06-18.((cite journal)): CS1 maint: multiple names: authors list (link)
• Fuller JR (May 10, 2007). "Fish fraud: The menus said snapper, but it wasn't!". Chicago Sun Times. Retrieved 2008-06-18.
• Gray, J. A. C. (1960). Amerika Samoa: History Of American Samoa And Its United States Naval Administration. Annapolis, Maryland: United States Naval Institute. ISBN 978-0870210747.
• Crasborn, José (2006). "Los patrones constructivos de Tak´alik Ab´aj" (PDF online edition). XIX Simposio de Investigaciones Arqueológicas en Guatemala, 2005 (Edited by J.P. Laporte, B. Arroyo and H. Mejía). Guatemala: Museo Nacional de Arqueología y Etnología: 45–55. Retrieved 2009-02-06. ((cite journal)): Unknown parameter |coauthors= ignored (|author= suggested) (help) (in Spanish)
• "Московское метро атаковано террористами. ФОТО. ВИДЕО" (in Russian). Top.rbc.ru. 2010-03-29. Retrieved 2010-03-29.
• "Pilsudski Bros". Time. 1930-04-07. Retrieved January 15, 2008. ((cite magazine)): Unknown parameter |lay-format= ignored (help)
• Mlakar Sr., Paul F. "Blast Loading and Response of Murrah Building" (PDF). Forensic Engineering. Retrieved June 26, 2009. ((cite web)): Check date values in: |accessdate= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
• Gray, Jonathan, Fordham University (2007). "Imagining America: The Simpsons Go Global". Popular Communication. Mahwah, New Jersey: Lawrence Erlbaum Associates, Inc. 5 (2): 129–148. doi:10.1080/15405700701294111. S2CID 143311566. Retrieved 2007-10-28.((cite journal)): CS1 maint: multiple names: authors list (link)
• Garcia, Michael O. (2005-09-20). "Geology, geochemistry and earthquake history of Lōʻihi Seamount, Hawaiʻi" (Document). School of Ocean and Earth Science and Technology. ((cite document)): Unknown parameter |accessdate= ignored (help); Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |format= ignored (help); Unknown parameter |url= ignored (help); Unknown parameter |version= ignored (help)
• Emery, K.O. (1955). "Submarine topography south of Hawaiʻi". Pacific Science. University of Hawaiʻi Press. 9: 286–91.
• Klein, F. (1982). "Earthquakes at Lōʻihi submarine volcano and the Hawaiian hot spot". Journal of Geophysical Research. 87: B9. doi:10.1029/JB087iB09p07719. ISSN 0148-0227.
• Guzmán, Julio Manuel L. (2010-06-30). "Tamaulipas suspende clases por 'Alex'". El Universal (in Spanish). Retrieved 2010-07-01.
• Kosmin, Barry A.; Keysar, Ariela (March 2009). American Religious Identification Survey 2008 Summary Report (PDF). Trinity College. p. 17. Retrieved 2009-03-15.
• "One for the Ages - Vince Young Leads Longhorns to the Fourth National Title". Dave Campbell's Texas Football. Host Communications Inc. January 2001. pp. 3–90.
• Wheelwright, Nathaniel T. (June 1985). "Competition for dispersers, and the timing of flowering and fruiting in a guild of tropical trees" (PDF). Oikos. Oikos, Vol. 44, No. 3. 44 (3): 465–77. doi:10.2307/3565788. JSTOR 3565788.((cite journal)): CS1 maint: date and year (link)