Siddur Sefard · Shabbat Morning Services, Blessing of New Month, Chapter 1
1
נכון לדעת זמן המולד קודם שמברכין החודש:
The following prayer יְהִי רָצוֹן, composed by Rav, head of the Babylonian yeshiva at Sura, is mentioned in the Talmud, (Maseches Berachos 16b), but not as a prayer specifically ordained for blessing the new month. It was actually a daily prayer that Rav recited each day after the regular service. The יְהִי רָצוֹן was adapted by Ashkenazi Jews as a prayer for the coming of the new month by adding the words: שֶׁתְּחַדֵשׁ עָלֵינוּ אֶת הַחוֹדֶשׁ הַזֶּה לְטוֹבָה וְלִבְרָכָה but Sephardic Jews omit the entire prayer as it is not mentioned either by Rambam or Avudraham.
נכון לדעת זמן המולד קודם שמברכין החודש:
The following prayer יְהִי רָצוֹן, composed by Rav, head of the Babylonian yeshiva at Sura, is mentioned in the Talmud, (Maseches Berachos 16b), but not as a prayer specifically ordained for blessing the new month. It was actually a daily prayer that Rav recited each day after the regular service. The יְהִי רָצוֹן was adapted by Ashkenazi Jews as a prayer for the coming of the new month by adding the words: שֶׁתְּחַדֵשׁ עָלֵינוּ אֶת הַחוֹדֶשׁ הַזֶּה לְטוֹבָה וְלִבְרָכָה but Sephardic Jews omit the entire prayer as it is not mentioned either by Rambam or Avudraham.