The phrase "a certain source" is correct and usable in written English.
It can be used when referring to a specific source that is not named or is unknown to the reader.
Example: "The information was obtained from a certain source that requested anonymity."
Alternatives: "a specific source" or "an unspecified source".
World leaders are due to meet next week in Canada for economic talks, and China's currency policies had appeared a certain source of conflict.
Each intermediate node decides whether it should retransmit or discard a packet that comes from a certain source node.
The process of taking compositional data and attributing a provenance from a certain source is not a trivial task [4].
Traditional IE techniques are limited to a certain source X (X = a particular language, domain, limited number of pre-defined fact types, single data modality, …).
With FriendFeed there were several more options, including hiding elements from just a certain source, as well as automatically unhiding items if a friend had "liked" it.
If information from a certain source is accepted as credible uniformly by a large number of users, quite possibly that source is credible.
Specifically, ALE has been utilized to evolve strains to better adapt to defined conditions, e.g., a certain carbon source, energy source, or to cope with environmental stress.
Depending on the nature of a problem, certain sources are of great value and are therefore considered of high quality, while other sources, although contributing to the production of intelligence, are supportive rather than critical in nature.
Radio tightly focuses on a certain sound source to the rigid exclusion of all others.
As seen in the results, the identification accuracy is not influenced by a specific image or video format in a certain video source.
Faces In The News suspects "Mayor Mike" refers to a certain news source… The $40 million Icahn Stadium will feature a 400-meter running track, a soccer field and seating for 10,000 people.
