Clapper Post, or Klapperpost in German, was an urban postal service in Vienna, the capital of Austria, and in some of the country's other cities, that began in 1772. Its name refers to a clapper (a type of rattle) with which mail carriers announced their arrival. In Vienna, it existed for more than ten years.^[1][2]

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  Clapper mailman (engraving; late 18th century)
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  A unique money letter with 50 florins in banknotes from Prague to the town councillors of Hungarian Skalitz (in today's Slovak Republic; 1783)

• Media related to Clapper Post at Wikimedia Commons
• "Clapper Post". Glossary of Stamp Collecting Terms. AskPhil; Collectors Club of Chicago. Archived from the original on 2009-03-08. Retrieved 2009-08-14.
• "Wiener Klapperpost". Philapedia. Das Lexikon der Philatelie (in German). Philapedia.de; Philatus, Briefmarken Peter Schapler. Archived from the original on 2009-10-12. Retrieved 2009-08-10.
• "Österreichisches Postgeschichte – Dr R Wurth with articles by Dr Christine Kainz". The APS Library (in German). Austrian Philatelic Society (APS). Archived from the original on 2011-07-03. Retrieved 2009-08-10.
• "Austro-Hungarian Empire". Stamp Atlas. Sandafayre Stamp Auctions. Retrieved 2009-08-11.
• "Exhibit: Austria 1783 – «Lesser» or «Clapper» Post from Prague". EXPONET. Virtual International Philatelic Exhibition. Japhila; Břetislav Janík. 2007-01-26. Retrieved 2009-08-14. Exhibitor: The Prague Postal Museum, Czech Republic
• "The Victorian police rattle mystery". Constabulary.com. Archived from the original on 2010-02-18. Retrieved 2009-02-05. Photos of similar rattles are given that were used by English police in the 19th century