The site that almost made me drop the Skyships.org project, it has so much information:
https://www.airships.net
Another site loaded with good information:
http://www.zeppelinhistory.com
A Shipload of Articles on Airships:
https://welweb.org/ThenandNow
Aiships: The Future That Never Was
Public Domain Image Resource - WOW!
* picryl.com - Search word Dirigible
http://www.blimpinfo.com/
http://www.madehow.com/Volume-3/Airship.html
https://www.vintag.es/2014/12/17-amazing-vintage-photos-of-airships.html
Earliest Dirigibles?:
https://welweb.org/ThenandNow/Danilewsky.html
- Shenandoa (ZR-1)
https://en.wikipedia.org/wiki/USS_Shenandoah_
- R-38 (ZR-2) US & UK
https://en.wikipedia.org/wiki/R38-class_airship
- Los Angeles (ZR-3)
https://en.wikipedia.org/wiki/USS_Los_Angeles_
- AKRON (ZR-4)
https://en.wikipedia.org/wiki/USS_Akron
https://www.onlyinyourstate.com/new-jersey/cursed-nj-airship/
https://www.onlyinyourstate.com/new-jersey/worst-disasters-us-nj/
https://www.airships.net/us-navy-rigid-airships/uss-akron-macon/
- MACON
http://self.gutenberg.org/articles/USS_Macon_
https://en.wikipedia.org/wiki/USS_Macon_