Third class of interplanetary type III fine structures. (a) Radio dynamic spectra observed on 30 November 2011 between 7:30 UT and 8:30 UT, including an irregular type III burst with fine structures at 07:52 UT by the STEREO A and STEREO B spacecraft. (b) Radio dynamic spectra observed on 12 November 2010, including stria-like fine structures within the type III bursts observed at 13:45 UT, and large heart-shaped substructure and stria substructure in the STEREO/WAVES observations.