Which of these characteristics of information make it undesi

Which of these characteristics of information make it undesirable to cite as a source in a technical paper:
a. The information comes from a published article with no references.
b. The information has been peer reviewed.
c. The credentials of the author of the information cannot be determined.
d. The information is confidential and cannot be made public.
e. Any of the above.

Solution

Lets look at the options

1. Information from published article with references . Possible to cite, as the work could be an original work with no references.

2. The information has been peer reviewed. There is nothing wrong in doing this also

3. The credential of the author of the information cannot be determined. In this case also one can cite the article with slight modification, in the author\'s name it would be \' Anonymous\' .

4. Confidential information : One cannot cite the information that is confidential without proper permission from the respected authority.