If you find information within a book or periodical you will want to cite the page, book and author, even the ISB number. This allows others to verify the information.
We have become so easily spun up on simple propaganda that sceptics among us now won't even research anything. It's all based on reputation and what the media who themselves never research anymore, anything or they will deliberately obfuscate the truth in order to defame a personality and his work. Robert F. Kennedy, Jr. it's a great example of this
We need solid references to the authority (author) of information, ideas and conclusions to give credit, investigate further or see that the source, himself, is compromised and may be leading in misdirection for the purpose of fostering ignorance.
It's no so much authoritarian worship (Fiat) but it is understanding who the author is and what he is trying to communicate. Running with an idea leads to speculation and that is fine if you are totally in the dark but the habit of citing sources will lead to the ability to assess your critics as incapable of critical thinking and you can dismiss them easily whereas a good critic may lead to insight for you and him with investigation of sources.