The study on which this article reports investigated the internationalisation of higher education studies by examining collaborations in the form of international co-authorships. We analyse how network-based mechanisms, related to structural relationship between authors (preferential attachment, i.e., higher tendency to collaborate among the most productive ones) and node level features (homophily, i.e., tendency to collaborate with similar others), affect higher education co-authorship networks. We build a bipartite co-authorship network based on 17,262 publications from 33 specialised higher education journals indexed in Scopus from 1996-2018. Scientific collaboration in higher education mainly occurs within national borders. We found that higher education is not an internationally oriented field of research, with around 90% single-country publications. A geographical divide was observed between the two largest communities (Europe, Asia and Oceania vs. the Americas) which was also reflected in the research themes addressed by these communities, structured around the known divide between (1) learning and teaching, and (2) policy-based studies. Preferential attachment was observed to be a network-based mechanism that contributes to drive the formation of new co-authorships. Similarly, homophily based on academic seniority and research productivity emerged as a significant explanatory mechanism. We present a methodology for disambiguating the names of higher education institutions. We demonstrate an associated effect on co-authorship networks. Our research and analysis support the effectiveness of the proposed method.