Hobson-Jobson: A glossary of colloquial Anglo-Indian words and phrases (1903 - searchable database)
Traci Nagle, Hobson-Jobson and Dictionaries of Indian English (book chapter, 2020)
Wikipedia: Glossary of the British Raj
James Lambert, Anglo-Indian slang in dictionaries on historical principles (article, 2018)
James Lambert, Indian English slang (book chapter, 2014)
S.N. Sridhar, Indian English (book chapter, 2020)
Pramod Pandey, Indian English Pronounciation (book chapter, 2015)
Ravinder Gargesh, Indian English: phonology (book chapter, 2004)
Pingali Sailaja, Introduction to Indian English (OED, 2022)
Wikipedia: Hinglish (Hindi/English)
The rise and rise of Hinglish in India (article, 2016)
Wikipedia: Kanglish (Kannada/English)
Wikipedia: Manglish (Malayalam/English)
Wikipedia: Tanglish (Tamil/English)
Wikipedia: Tenglish (Telugu/English)