Somewhere on the net I found Spanish lyrics for "Maria Elena" which include a six-line introduction beginning:

Quiero cantarte mujer
mi más bonita canción

I assume these belong to Barcelata's original (1925), though none of the recordings I've heard (bilingual or English-only) include it. If someone has Barcelata's sheet music, please let me know how the introductory melody goes, via ABC, a dot scan, a MIDI link or some other means. Thanks in advance.