Many travelers get stuck in the jungle of connection systems and adapters for propane, butane and LPG when they try to fill their containers abroad. Systems differ per country and within countries often multiple systems exists. Furthermore travelers need to be prepared for various filling methods such as cylinder filling, automotive filling stations and even gravity filling, all requiring their own systems.
I initiated creation of a document to bring data about connection standards per country together. Here is the link to it.
It is still very much work in progress, so additions and corrections are most welcome!