Philatelic Links
British
Library, Philatelic Collections: http://www.bl.uk/collections/philatelic
Classical Polar Postal History: http://www.south-pole.com/

Guide to Stamp Collecting: https://www.swagbucks.com/shop/guide-stamp-collecting
Philatelistische Bibliothek
München: http://www.muenchner-stadtbibliothek.de/philatelistische-bibliothek
Postal History Society: http://www.postalhistory.org.uk/php/index.phpPostal Museum, London: https://www.postalmuseum.org/