a heat source.
a source of carbon dioxide.
an infectious agent depends on a reservoir for its survival.
communism's Russian root.
he carried an armful of references back to his desk.
he spent hours looking for the source of that quotation.
he was the generator of several complaints.
Jupiter was the origin of the radiation.
Pittsburgh is the source of the Ohio River.
She sourced a supply of carpet.
the Italian beginning of the Renaissance.
the reporter had two sources for the story.
The writer carefully sourced her report.
They are sourcing from smaller companies.