Recursive make in subdirectories

Question

How can I order make command in the Makefile to execute recursively in all subdirectories make commands (defined in the Makefile in the subdirectories)

Answer 1

1. Read Recursive Use of Make chapter of GNU Make manual.
2. Learn Peter Miller's Recursive Make Considered Harmful article.
3. ...
4. PROFIT!!!

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P.S. A code snippet from my answer to a different yet related question could be used as a rough approximation.