German, C., and N. C. Nanda. “Incremental Value of Three-Dimensional Echocardiography over Two-Dimensional Echocardiography in the Assessment of Atrial Septal Defects”. Cardiovascular Journal, vol. 7, no. 2, Feb. 2015, pp. 67-71, doi:10.3329/cardio.v7i2.22243.