That "intro" to Kashmir (originally titled Swan Song) was scrapped from Physical Grafitti. It is on the studio outtakes though. Page would later rehash that intro when w/ Paul Rogers in The Firm for a tune called Midnight Moonlight. A tune he would use to showcase White Summer live on Firm tours. Love DADGAD!
And for an acoustic version of White Summer from Page's prime (by 89, he'd had two hand injuries, one resulting in permanent tendon damage, plus years of addiction....sadly his acoustic playing suffered)
The video master of this version is damaged, but the sound is much better...and the performance red hot!!