The American Heritage® Dictionary of the English Language: Fourth Edition. 2000.
Appendix I
Indo-European Roots
ENTRY:
bhegw-
DEFINITION:
To run. 1.beck2, from Old Norse bekkr, a stream, from Germanic *bakjaz, a stream. 2.–phobe, –phobia, from Greek phobos, panic, flight, fear, from phebesthai, to flee in terror. (Pokorny bheg- 116.)
- 116.) 
