Depends on how you define "source."
When I work on a problem or issue, these are the sources I use:
1) My own experiences
2) The people who are experiencing the problem or issue.
3) Other experts.
4) Printed reference material.
5) Public forums where problems are discussed.
When I work on a problem or issue, these are the sources I use:
1) My own experiences
2) The people who are experiencing the problem or issue.
3) Other experts.
4) Printed reference material.
5) Public forums where problems are discussed.