Social communities represent a constant source of real-time feedback that can give business leaders valuable information to improve future products and services information that previously would have taken considerable time, effort, and expense to collect.

FORBES: Why Social Media Is One Of The Best Ways To Keep Your Customers Happy

"He's been a constant source of inspiration for the project, " the Biophilia project co-ordinator James Merry said.

BBC: Bjork opens Manchester International Festival

And Hancock and his descendants served as a constant source of conversation between my father and me, a vital link between us when, class-wise, and in every other wise, each year placed us farther apart.

NEWYORKER: Dead Man Laughing

Virtually all measures of academic achievement have shown substantial differences in the performance of African-American and white students in the United States, and these performance differentials have been a source of constant analysis and discussion.

UNESCO: II Part Analytic Section