Bunnell, S.: Opposition of the thumb. J. Bone Joint Surg. Am., 20: 268-284, 1938.
Foucher, G., Malizos, C., Sammut, D., et al.: Primary palmaris longus transfer as an opponensplasty in carpal tunnel release: a series of 73 cases. J. Hand Surg., 16: 56-60, 1991.
Kapandji, A.: Clinical test of apposition and counter-apposition of the thumb. Ann. Chir. Main, 5: 67-73, 1986.