Liang Zhang Carlos Vázquez Wa James Tam Demin Wang Zerotree data structure for 4D wavelet coefficient coding. 737-740 2008 ICME http://dx.doi.org/10.1109/ICME.2008.4607540 conf/icmcs/2008 db/conf/icmcs/icme2008.html#ZhangVTW08