Concept of Keystone Species in Web Systems: Identifying Small Yet Influential Online Bulletin Board Threads. - Shota Ejima; Mizuki Oka; Takashi Ikegami (WebSci, 2019)

Web as an Evolutionary Ecosystem: Emergence of Keystone Species. - Palin Choviwatana; Shota Ejima; Mizuki Oka; Takashi Ikegami (ALIFE, 2020)