Gupta, Savita; Kaur, Lakhwinder: 'Wavelet despeckle filtering' (Healthcare Technologies, 2018), 'Handbook of Speckle Filtering and Tracking in Cardiovascular Ultrasound Imaging and Video', Chap. 9, pp. 173-199, DOI: 10.1049/PBHE013E_ch9
IET Digital Library, https://digital-library.theiet.org/;jsessionid=3944uu279hm82.x-iet-live-01content/books/10.1049/pbhe013e_ch9