1. Oryoji A, Kawara T, Hara H, Aoyagi S, Kosuga K, Ohishi K. Left atrial free-floating ball thrombus in a patient without mitral valve disease. Nippon Kyobu Geka Gakkai Zasshi. 1993; 41: 699–703.
2. Aoyagi S, Kosuga K, Hisatomi K, Shima H, Tanaka I, Shimadu S, Ohishi K. Four successfully operated cases of ball thrombus in the left atrium. (Article in Japanese) Kyobu Geka. 1989; 42: 97–102.
3. Kaneda T, Iemura J, Michihata I, Zhang ZW, Oka H, Otaki M, et al. Two cases of a free floating ball thrombus in the left atrium. Circ J. 2002; 66: 869–871.
4. Doiguchi M, Ikei S, Mizutani M, Haga K, Arai M, Yamashita S. Mitral valve stenosis associated with a floating ball thrombus in the left atrium; report of a case. Kyobu Geka. 2002; 55: 585–587.
5. Misumi T, Kudo M, Ito T, Matsubara T, Kumamaru H. Floating ball thrombus in the left atrium with mitral stenosis. JPN J Thorac cardiovasc Surg. 2003; 51: 387–389.