History - Oremus pro Pontifice
Jul 16, 2017 (abloomfield)
add liber usualis as source
sources
[{"chant_id":"3033","source":"3","page":"1866","sequence":"1","extent":"1"},{"chant_id":"3033","source":"5","page":"123","sequence":"1","extent":"1"},{"chant_id":"3033","source":"10","page":"230*","sequence":"3","extent":"2"}]