History - Haec est virgo

Oct 30, 2018 (SirPL)

Added reference to Graduale Romanum 1974

sources
[{"chant_id":"500","source":"2","page":"[57]","sequence":"1","extent":"1"},{"chant_id":"500","source":"3","page":"1222","sequence":"1","extent":"2"},{"chant_id":"500","source":"4","page":"501","sequence":"1","extent":"1"}]