The phrase "an existing source" is correct and usable in written English.
It can be used when referring to a source of information, data, or materials that is currently available or already in existence.
Example: "In order to support our research, we need to reference an existing source that provides credible data on the topic."
Alternatives: "a current source" or "an available source".
Most people used digital data from an existing source - websites, clearinghouse, existing digital source.
Under a number of CAA programs, an existing source which is completely or substantially rebuilt is treated as a new source.
This is all you need to know if you've been puzzled by the nomination of "O Brother, Where Art Thou?" for the Oscar for best screenplay from an existing source.
First we obtain a set of known well-formed useful phrases from an existing source and label these phrases as positive.
(i) Emissions reductions achieved by shutting down an existing source or curtailing production or operating hours may be generally credited for offsets if they meet the requirements in paragraphs IV.C.3.i.1.
This enables an existing source of condition monitoring data to be analysed in a rapid and repeatable manner, providing additional information relating to core health on a more regular basis than routine inspection data allows.
We first propose a realistic semi-global eavesdropping attack model and show its effectiveness in compromising an existing source-location preserving technique.
A user identifies any existing sources of workload data, for example, from database monitoring tools.
Deployment of the control technology on a new or existing source with similar gas stream characteristics is generally a sufficient basis for concluding the technology is technically feasible barring a demonstration to the contrary as described below.
For myself, I went through files of old newspapers finding advertisements for gigs, ebay-ed old periodicals, googled like a madman, in an attempt to construct a chronology from existing sources.
This step includes acquiring data from a variety of existing sources and implementing a custom machine learning model.
