Star Wars Stuff: The Inspiration for the AT-ATs

What gave the creators of Star Wars Episode V: The Empire Strikes Back the inspiration which produced the great, lumbering AT-ATs?  According to Phil Tippett -- Visual Effects designer for ESB and the AT-AT -- it was the largest known land mammal to have ever existed.  A distant cousin of the modern-day rhinoceros: Paraceratherium

This mega-creature also goes by the names: Indricotherium and Baluchitherium.  The "therium" part always means "beast."  I love etymology.  The best I can do with "Paraceratherium" is: "Pre-horned-beast."  My google skills did not produce a source translation.  Apparently, the first name given to any bones later determined to be this animal was Paraceratherium.  "Indricotherium" and "Baluchitherium" came later.  As with most new pre-historic megafauna discoveries, it takes a few tries before they get it right, or realize previously discovered bones were the same as a set thought new.  Triceratops' first discovered skull was thought to be of a great bison.  /digress

Back on topic: a popular myth is that the AT-AT was instead inspired by cranes operating on the docks at Oakland, CA.

However:

"[This is] a myth both Lucas and visual effects expert Phil Tippett deny. The inspiration for the AT-AT was Paraceratherium, an extinct species of rhino-like creature and the biggest land mammal in history." Source

I found a great youtube vid/BBC documentary on Paraceratherium:

This thing was huge.  It would make the biggest elephant look small.  Up to 18 tons, 16 feet tall with a total span from tail to nose of some 40 feet.

Great pic showing size of Paraceratherium,
which dominates the frame in the background.

What an AT-AT may look like.

Somebody did this.