1. Co-existence of the pectoralis quartus and pectoralis intermedius muscles;Arican;Morphologie,2006
2. The manner of insertion of the pectoralis major muscle in man;Ashley;Anat Rec,1952
3. Doubled pectoralis quartus, axillary arch, chondroepitrochlearis, and the twist of the tendon of pectoralis major;Bergman;Anat Anz,1991
4. Homology and innervation of the achselbogen and pectoralis quartus, and the nature of the lateral cutaneous nerve of the thorax;Birmingham;J Anat Physiol,1889