In particular In the second interval both A and B should be flatted in the third there is no G in the original tetrachord in the fourth and fifth there is no B natural in the original tetrachord in the sixth there is no A natural in the original tetrachord  Im also not aware of Webern or Schoenberg using this tetrachord much explicitly  There might be a few of them here or there in their music but Im pretty sure its not a significant feature of eithers music as it certainly is in Carter I dont know about Perle  I dont think either Webern or Schoenberg even knew of the special properties of this tetrachord  The literature on Webern and Schoenberg that I know certainly doesnt mention this  Mind providing citations  Finally the second External Link is dead  Its also questionable Carters Night Fantasies is usually cited as the quintessential example of registrally deployed allinterval twelvetone series quite a different phenomenon than allinterval tetrachords  There might be allinterval tetrachords within it though  itd be nice to have the link fixed so we can see