REFERENCES.md

C++ Reference

• string
• string::substr
• string::compare
• isalpha
• ispunct

C++ Forum

• Using cin to get user input.
• getline and wchar_t

Stack Overflow

• c++ - Passing std::string by Value or Reference
• Another C++ learning moment: returning strings from functions
• c++ - How to append a char to a std::string?
• bash - How to change the output color of echo in Linux
• Case-insensitive string comparison in C++
• c - warning: multi-character character constant [-Wmultichar]

Misc

• Bool data type in C++ - GeeksforGeeks
• c++ - What is a 'Null Terminated String' ? - Software Engineering Stack Exchange
• std::size_t - cppreference.com
• IBM Knowledge Center - Pass by reference (C++ only)
• C++ for loop
• What English sentences contain repeated, consecutive words? - Quora
• BASH Programming - Introduction HOW-TO: Loops for, while and until
• What size wchar_t do I need for Unicode?