(A) History of IM–MS and Tandem-IM publications, from searches on Web of Science for topics: IM–MS; Tandem-IM. Astrices represent where there were fewer than 10 publications per year (B) Timeline of advances of IM, IM–MS and Tandem-IM, with the dating from 1960–2020. References, in chronological order: [16, 25, 27, 29, 30, 32, 33, 35, 38–49].