 What does the title BBB refer to?
I sometimes refer to their overlap or common ground as the BBB definition of OA. My definition here is the BBB definition reduced to its essential elements and refined with some post-BBB terminology (green, gold, gratis, libre) for speaking precisely about subspecies of OA. Note that all three legs of the BBB definition go beyond removing price barriers to removing permission barriers, or beyond gratis OA to libre OA. In principle, any kind of digital content can be OA, since any digital content can be put online without price or permission barriers. Moreover, any kind of content can be digital: texts, data, images, audio, video, multimedia, and executable code.
 The cities where most of the early meetings were held
 The type of certification a journal needs to be an OA venue  The Bureau in charge of decisions about OA  The cities where most of the early meetings were held  An organization beting developed to gather public opinion about OA