Question

Could someone help me find reliable websites (not Wikipedia, etc) that explains that ribosomes are membrane-bound organelles?

Answer 1

These university (edu.) websites explain ribosomes and organelles.

http://micro.magnet.fsu.edu/cells/ribosomes/ribosomes.html

http://biology.clc.uc.edu/courses/bio104/cells.htm

http://askabiologist.asu.edu/research/buildingblocks/cellparts.html