Contraction of what skeletal muscles allow for inhalation of air into the lungs

The muscles which make the lungs to expand and so, to inhale air into them are diaphragm and external intercostals muscles. Contraction of the diaphragm causes an increase in the size of the thoracic cavity, while contraction of the external intercostal muscles elevates the ribs and sternum, but the only skeletal muscles from those two aforementioned are external intercostal muscles