Data Science Further Reading
Aus MattWiki
This article contains a list of notably good sources on different topics.
Data Types
https://towardsdatascience.com/data-types-in-statistics-347e152e8bee
https://www.mymarketresearchmethods.com/types-of-data-nominal-ordinal-interval-ratio/
Feature Engineering
https://towardsdatascience.com/feature-engineering-for-machine-learning-3a5e293a5114 (With Python)