I'm not much of a RS fan, they themselves have issues with plagiarism and have never been the hallowed pinnacle of truths. I wouldn't quite say they "took them to the woodshed" when they mention in the article the times Zep did give songwriting credit to a few of the songs, at least one of which was public domain. Most of what they listed is well known and has been addressed even by Page and Plant. After all, it pays more to sue a bigger band when they have sold more records. As a side note, it's obvious to me they used Spirits Taurus almost note for note. How they won that case is beyond me. It's always been a concern and discussion where that fine line of inspiration and creation is in music. Alongside the ethical and reputational aspects of when to credit versus an inspiration/homage comes the huge issue of Record Company interests in seeking royalties. As always, money is involved. These issues also coincide with the availability and distribution of music which increased dramatically during the 50's and especially the '60's. Things like this when unnoticed much more when an artist heard a minstrel show pass through town and copied a song and then had "fame" in their own circles. Audiences were mainly regional at that time and had no exposure to the other artists and their songs. This one of the main reasons I built my site, to look back at the evolutions and connections that resulted in the music we grew up with. I was fortunate to have grown up in the '60's and had listened to the radio since the late 50's as a kid and witnessed the marked change that occurred. Seeing the Beatles on Ed Sullivan that first time (the only live appearance - the rest were taped) changed my life and I've never looked back. Well, I have payed little attention since the '80's, Disco still Sucks!