Any body know where I can find good Nephilim sources outside the Biblical sources?

Lately I've been conducting research on the Nephilim (see Genesis 6:4), their fathers and any connection they may have with the legends of Atlantis. But I've run into a lot of what seems to be pseudo historic/religious material. Does anyone know about reliable sources on this subject that dont input any pseudo theories like the Nephilim being aliens or Atlantis being enemies of Lemuria (Lemuria by the way was only presented as a possible land bridge between Madagascar and India to explain why both regions have similar species of Lemurs, hence the name, and plants). If anyone has reliable sources I would be very appreciative. Thank you.