While creating this website I dug through hundreds of websites, saw thousands of photos (and made my own), talk to many people. Photos used on this website come from eBay auctions, Facebook groups, Flickr profiles, websites and many other sources I found. It's impossible to list everything but all were copied for educational purposes only.
Additionaly, I've gathered some interesting websites I can recommend:
 

• Memorabid.com - amazing place to buy match worn / issue shirts and other items.
   

• Tianse17 - shirt collector from Poland. With great collection comes great knowledge. And he shares it in his articles!
   

• Footyheadlines.com - great source for upcoming boot and kit releases. Lots of information about shirts and patches.
   

• Collectors on Instagram:
  Juventus collection by Szarancz
  Unique Juventus shirts
  piter_1980
  dutto996_match_worn_shirts