::Sorry it has taken so long to find a solution to this, but then working through the references is a pretty big job. I think the webcite used to support this is not a reliable source. I tried to find other sources and I think I see where this "fact" came from. Storm Thorgerson's book on Hipgnosis Walk away René: an ABC of the work of Hipgnosis (1978) says that "Flash Knickers was banned in Franco's Spain and allegedly Houses of the Holy, was thought immoral and depraved in Kansas", but the 2010 book For the love of vinyl: the album art of Hipgnosi credited to Aubrey Powell and Storm Thorgerson, says "apparently this cover was banned in Spain and Middle America". It looks to me as if the story has grown over the years. Interestingly Wall says nothing about bans (and you kind of think he would), but does mention the controversy. In short, I suggest this is unsafe and we should avoid repeating a likely myth. Accordingly I will change this to a short mention of the controversy, citing Wall in the next batch of reference cleanups, unless there are reasoned objections here.'''