add tenzing for CRediT

docs/ACKNOWLEDGEMENTS.md

@@ -32,4 +32,8 @@ The Git and GitLab tutorials have been recreated from material developed for the
 
 `Cassandra Gould van Praag. (2020). cassgvp/git-for-collaborative-documentation: OxBe 2020 (v1.0.1). Zenodo. https://doi.org/10.5281/zenodo.4058254`
 
+We promote the use of the [Tenzing webapp](https://rollercoaster.shinyapps.io/tenzing/) for creating [CRediT](https://casrai.org/credit/) author statements. 🙏
+
+`Holcombe, A. O., Kovacs, M., Aust, F., & Aczel, B. (2020). Documenting contributions to scholarly articles using CRediT and tenzing. Plos one, 15(12), e0244611.`
+
 Figures have been created from images in the [Noun Project](https://thenounproject.com) repository, contributed by [Alice Design](https://thenounproject.com/rose-alice-design/), [Andrejs Kirma](https://thenounproject.com/andrejs/), [DinosoftLab](https://thenounproject.com/dinosoftlab/), [Luis Prado](https://thenounproject.com/Luis/), [Sergey Demushkin](https://thenounproject.com/mockturtle/), [Thuy Nguyen](https://thenounproject.com/milkghost/), [vectlab](https://thenounproject.com/vectlabmail/), and [Victor Llavata Bartual](https://thenounproject.com/victor.llavata/). 🙏