Preprint manuscript for a study using the biphasic stimulus is available from PsyArXiv: [https://psyarxiv.com/e3wdv/][1]
This paper has been published from PLOS ONE (Aug. 30, 2021)
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0256712
[1]: https://psyarxiv.com/e3wdv/