- Abhishek Bhuwalka manages a very useful website on Philatelic Literature, including a section on India: Airmails and Maritime. This lists many publications on the subject.
- Indian Philately Digest has published International Postal Rates from India from 15 August 1947 to 1 April 1957. Very useful information to any Indian Airmails collector.
- Philatelic Bibliopole Catalog of Philatelic Books and Literature; New and Usedpbbooks.com/: Len Hartman is one of the most helpful dealers of Philatelic Books. He carries a vast inventory including several out of print editions. Here is a link to his website with an exhaustive listing of titles available with him. http://pbbooks.com/
- Collector Bazar online platform where you can buy and sell all kinds of collectible items like Stamps, Coins, Banknotes, Publications, Collectible and many more things.
- R101 - The Final Trials and Loss of the Ship: Over the summer of 1930, the R101 lay in the Number 1 shed at Cardington undergoing extensive modifications, which were needed following on from her 1929 and early 1930 trial flights.
- Control, Response and Crash of HMA R.101. Research paper published in the Journal of Aeronautical History by Bryan Lawton.
- The Great Britain Philatelic Society has posted a superb reference set of English language versions of UPU Conventions and Related Documents, from the Berne Treaty of 1874 through to the Extraordinary Congress of 2019.
- The Catapult Mail. During the late 1920s and early 1930s, the need for greater speed across Atlantic was recognized in the carriage of mail between Europe and the Americas. It is an interesting story of man's bringing together the knowledge learned from sailing the sea and flying in the air for the benefit of man's needs, as mail could be carried in the last leg by an airplane launched from a ship while still at sea. (Courtesy: Rainbow Stamp News, Monthly e-stamp magazine Dehradun, January 2021, Vol.XIII No.157)