In the linked article it says that Babe I'm Gonna Leave You is credited to Bredon, Page etc. May I point out that this is only the case on recent CD issues. On the original vynyl and early CDs there is no mention of Bredon.

I saw Robert Plant at Canterbury Fayre a couple of years ago and he openly said that they ripped off most of their songs not thinking that anybody would notice. He went on to credit the original composeres for most of his set which included the most well known Zep ripoffs. Fair play Robert - you obviously don't care now cos you're stinking rich and most of the original writers have snuffed it anyway!