[1] Hatle L., Angelsen B.A.J.: "Doppler Ultrasound in Cardiology - Physical Principles and Clinical Applications". Lea & Febiger, Philadelphia, 2nd Ed. 1986, 220 pages.

    Translated to French: Hatle L., Angelsen B.A.J.: "Echocardiographie Doppler en cardiologie-Principes physiques et applications cliniques." Editions Vigot, 1986.

    Translated to Japanese by Nishimura Co., Ltd 1995.

    [2] Angelsen B. A. J.: "Ultrasound Imaging - Waves, Signals, and Signal Processing". 2 volumes, 1416 pages, Emantec, Trondheim. 2000.