- Handout on What is a Series - Part I (Maynooth University)
- Handout on What is a Series - Part II (Maynooth University)
- Handout on What is a Series - Part III (Maynooth University)
- Videos & Notes on Sigma Notation (mathcentre)
- Notes on Series - Basics (Paul's Online Notes)
- Video on Sigma Notation (Patrick JMT)
- Video on What is a Series (Patrick JMT)
