Find a written documentation of the commonly-accepted model either by researching it at a library or looking it up with a computer that has Internet access. Search for the model name in references using different variations of the name.
Look for sources that discuss the history of the model and how it came to be. Pay particular attention to those sources that have academic credentials. Write all your sources down that directly discuss the model, its history, and its basis of use. Try to find and record at least five different sources. Avoid using opinion articles, blogs, or popular media periodicals. Look for such sources in news periodicals, studies, books, and scientific reports.
Err on the side of using more sources rather than not enough. Edit out additional sources later when you need to condense your own written work for space limitations.
Confirm that you have copyright permission to use the source once you have found it. If not clearly allowed, contact the publisher of the source by email, phone or written letter asking for permission of use. Document and keep the permission provided on file.
Cross-check your sources to make sure they agree on the same conclusions. Adjust your own writing to document differences if the sources do not agree on one common perspective.