In attesa che venga aggiornato il link in TESTATA alla HOME PAGE del Sito
apro questo thread un po' più aggiornato che può tornare utile :
https://www.hipstamp.com/category/united-states
http://stampstock.com/index.php?main_page=index&manufacturers_id=37
https://www.mimir.se/htmlhome.aspx
https://picclick.it/Francobolli/Africa/Congo/?q=1982
http://francobollitematici.com/en/ajman-mint/2760-ajman-1972-1864-919-military-uniform-yellow-56-stamps-mnh.html
http://www.postalhistory.com/index.htm
ASTE:
https://www.philasearch.com/en/index.html
https://stamporama.com/auction/auction_main.php?action=40&id=RA/kkNtQ3fEus
http://www.filsam.com/default.asp?pag=vista&keywords=&spec=&idn=3586&idc=102&start=1
https://stampauctionnetwork.com/auctions.cfm
http://www.pac-auction.com/
http://www.laserinvest.com/
LIBRETTI:
http://www.booklets.nl/en/
Pietro