Trung Bộ Kinh (Majjhima Nikaya) 3:77
SUJATOKathaṁ bhāvitā ca, bhikkhave, ānāpānassati kathaṁ bahulīkatā cattāro satipaṭṭhāne paripūreti?
And how is mindfulness of breathing developed and cultivated so as to fulfill the four kinds of mindfulness meditation?