Cardinal Amleto Cicognani wrote to Cardinals Ottaviani and Cento, respective presidents of the Doctrinal Commission and the Lay Apostolate Commission, requesting them to launch the work under the banner of the new ‘Mixed Commission.’
SOURCE
Stefan Gigacz, The Leaven in the Council, Chap. 9, The Three Truths in Gaudium et Spes
A meeting of the new conciliar Coordination Commission held in Rome from 21-27 January, 1963, discussed a proposal from German Bishop Franz Hengsbach for a joint schema based on material from the preparatory Doctrinal and Lay Apostolate Commissions.
Belgian Cardinal Léon-Joseph Suenens proposed that a Joint or Mixed Commission be created to prepare this new schema.
SOURCE
Stefan Gigacz, The Leaven in the Council, Chap. 9, The Three Truths in Gaudium et Spes