[6] L. A. Feldkamp, L. C. Danis, J. W. Kress. Practical cone-beam algorithm[J]. J. Opt. Soc. Am., 1984, 1(6): 612~619
[7] Marc Kachelrieb, Katia Sourbelle, Willi A. Kalender. Empirical cupping correction: A first-order raw data precorrection for cone-beam computed tomography[J]. Meical Physics, 2006, 33(5): 1269~1274
[8] Hengyong Yu, Ge Wang. Feldkamp-type VOI reconstruction from super-short-scan cone-beam data[J]. Medical Physics, 2004, 31(6): 1357~1362