Academic websites, medical journals and government health websites are all very strong and reliable sources to learn more about vitamin B12. Often, these websites and journals are peer-reviewed and have been approved by qualified health professionals, which make them trustworthy.
Academic websites such as the Linus Pauling Institute at Oregon State University use a website URL that ends in ".edu." This is a reliable way to tell that its origins are from an academic institution. These websites, along with government-run websites such as the United States Department of Agriculture, are reviewed much more often than websites that end in ".com." Medical Journals and encyclopedias are often the best resources for learning more about vitamins such as vitamin B12, as they are written by medical professionals for the sake of teaching others about this type of information. All of these resources are purely factual and do not attempt to convince the reader to follow certain behaviors or practices.