Hilchos Rosh Chodesh, Siman Taf Yud Ches, Seif Aleph. Ten minutes exploring the text, Perek Shishi of Sha'ar Haknia, part one., Rosh Hodesh, Sefer Mishna Brura, Chapter 6, Siman 418, Seif 1, Shulchan Aruch Orach Chaim

Rabbi Gabi Fried