Bittmann, Felix. "Frontmatter". Stata: A Really Short Introduction, Berlin, Boston: De Gruyter Oldenbourg, 2019, pp. I-IV. https://doi.org/10.1515/9783110617160-fm
Bittmann, F. (2019). Frontmatter. In Stata: A Really Short Introduction (pp. I-IV). Berlin, Boston: De Gruyter Oldenbourg. https://doi.org/10.1515/9783110617160-fm
Bittmann, Felix. "Frontmatter" In Stata: A Really Short Introduction, I-IV. Berlin, Boston: De Gruyter Oldenbourg, 2019. https://doi.org/10.1515/9783110617160-fm
