M. Friedmann was the first to maintain, in his introduction to the Mekilta of R. Ismael (pp. 54 et seq., Vienna, 1870), that, in addition to R. Ishmael's work, there was a halakic midrash to Exodus by R. Simeon, which was called the "Mekilta de-R. Shim'on," and that this Mekilta formed part of the Sifre mentioned in the Talmud Babli (Sanh. 86a; Ber. 47b; Meg. 28b; Ḳid. 49a; Sheb. 41b); Ḥag. 3a).