From: Rabbi Moshe Sofer
To: Rabbi Zalman Leib Grinsfeld
May a man who has not yet fulfilled pru u'rvu marry during the three days of Hagbalah (3rd–5th Sivan), when some communities extend Sefirah mourning through those days? The Chasam Sofer leans toward leniency in small communities.
Source: Shu"t Chasam Sofer OC §142