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Surprisingly, on page #1278, in the index entry "Torsion", the 3 authors claim that "(torsion) not present in affine connection if equivalence principle is valid" and hint further to page #250 where they don't debate on it.

However, this assertion is terribly wrong, as Milutin Blagoevic' quoting [1] on page #66 of his book ("Gravitation and gauge symmetries") states after proving.

Surely, they wrote the book 3 years before the proof, but anyways, how could they do that ? They were already aware of both Cartan's theory (GR with torsion) and Lorentz gauge theory pioneered by Utiyama in his groundbreaking article in 1956 and refined by Sciama & Kibble.

Daniel.

[1]P von der Heyde [1975] "The equivalence principle in the [itex] U_{4} [/itex] theory of gravity",

*Nuovo Cim. Lett.*

**14**, 250.