NIST series publications, can be identified via the NIST Research Library's online catalog. Some NIST publications, including Special Publications, Technical Notes, etc., are freely available electronically, or copies can be loaned out or requested electronically.
For more information about types of NIST series publications: Types of NIST Publications
The NIST Publications Portal is another way to locate NIST publications. There you will find links to publication databases specific to the NIST laboratories which represent broad areas of research such as chemistry, physics, information technology, and materials science.
The Journal of Research of the National Institute of Standards and Technology, is freely available to the public. Full text articles back to 1948 are currently available; extended coverage will be forthcoming.
Also, search the NIST Digital Archives (NDA) for the full-text publications, including the Journal of Research and selected series publications.
Some popular collections of NIST publications:

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