Question About Vehicle Textures

Just have a question and hope this is the right place. I'm learning to make livery's, for personal use right now but thinking down the road to release if I get good enough. My question is I know I can upload texture without vehicle but if I wanted to add the vehicle, that belonged to someone else what would be the proper procedure. I'm guessing I would need the authors permission and or give them credit on my uploaded texture?  

Thanks in advance for any info.