My old copy of Baker's has the following sketchy info:
"Anna El-Tour, Russian soprano; b. Odessa, June 4, 1886; d. Amsterdam,
May 30, 1954. She studied at the St. Petersburg Cons. (voice with
Mme. von Hecke; piano with Essipova). From 1913-20, she taught in
Moscow; then left Russia; from 1922-25 was in Berlin; 1925-48, taught
at the Conservatoire International de Paris. After 1948, she was
professor of singing at the Amsterdam Cons. She traveled widely in
the Far East; gave recitals in Israel in 1953."
I hope this is of some help to you.
Dick Hihn