6.5 Referencias
R for Data Science. Capítulo 3 Data visualisation. G. Growlemund and H. Wickham. 1st Edition. O’Reilly J. 2016. http://r4ds.had.co.nz/data-visualisation.html
Tidy Data. H. Wickham. Journal of Statistical Software. August 2014, Volume 59, Issue 10. https://www.jstatsoft.org/article/view/v059i10
Data Wrangling with tidyr and dplyr - Cheat Sheet. Septiembre 2016. https://www.rstudio.com/wp-content/uploads/2015/02/data-wrangling-cheatsheet.pdf
Cheatsheet for **dplyr* Join Functions. Septiembre 2016. http://stat545.com/bit001_dplyr-cheatsheet.html
Data Transformation Cheat Sheet. Rstudio Resources. Enero 2017. https://www.rstudio.com/resources/cheatsheets/