https://www.salon.com/2018/11/16/master-excel-and-crunch-data-with-this-masterclass-course/
https://www.salon.com/2019/01/20/automate-tasks-in-excel-with-by-mastering-vba/
https://lifehacker.com/how-to-master-microsoft-office-excel-1767973710
https://www.inverse.com/article/46124-excel-certification-bundle-deal
good excel training 