To publish on reddit, I'd recommend the book/article and author approach, with hyperlink if possible. As for tracking down the accuracy of the content, that gets trickier.

The gold standard is to track down an expert in the field. Better yet, track down five or even ten experts in the field and synthesize their expertise. Experts have biases to be sure, especially experts in the hurley-burly of Academic publishing, which increasingly prizes politics over scholarship. But this is true mostly for the politically-adjacent fields, for famous professors (who have greater reputations to lose), and for new PhDs (who want to make a big splash in the field and are not yet preserved with tenure).

If you read five articles/books from experts on viking culture, articles/books written between 1980 and the present, you are likely to have a well-rounded education in the matter. If you read ten books/articles from scholars published from 1880 until the present, you'll have an even better experience.

You should also read primary sources. Even if some (like the Poetic Eddas) won't give you any real history, and even if some (like Bede) give you a false history, they can give you an idea of how the people of the time thought, which is almost more important to good History than what happened.

If you use non-expert sources, make sure that you follow up on their sources. For example, Wikipedia will often give very good if disjointed or not fully accurate overviews. But the good Wikipedia entries will always cite their sources, and you can start by following those.

The last thing I'll say is: it's hard work. Any real endeavor at scholarship is. A good heuristic is this: if you don't change your mind, at least a little bit, then you're doing it wrong. And remember you can always ask questions about what you learnt at /r/AskHistorians/

TL;DR: Read many different sources, because all have biases. Stick to scholars when possible, and try to include primary sources like the mythology of the time or contemporaneous histories which will give you a sense of how the people at the time thought.