Mapping Modern Science Using Co-citation Analysis. - Ayaka Saka; Masatsura Igami (IV, 2007)

Exploration of the evolution of nanotechnology via mapping of patent applications. - Masatsura Igami (Scientometrics, 2008)

Decreasing diversity in Japanese science, evidence from in-depth analyses of science maps. - Masatsura Igami; Ayaka Saka (Scientometrics, 2016)

Introducing a novelty indicator for scientific research: validating the knowledge-based combinatorial approach. - Kuniko Matsumoto; Sotaro Shibayama; Byeongwoo Kang; Masatsura Igami (Scientometrics, 2021)