Thanks app.
I sent an inquiry to that e-mail address last night and I've already received a reply! I, too, noticed the discrepancy between what was listed on the original website I was reading and the official paper's title. And now I know why that discrepancy exists. It is because the file Steven Summerfelt sent has a filename of "Summerfelt et al. 1993. continuous culture & selective harvest. Techniques for Modern Aquaculture, p 581-595.PDF" I suppose the official title of the paper is kind of long to use as a filename. So now it all makes sense.
Steven was also kind/proactive enough to send me another, more recent (2009), somewhat related article entitled "Advances in fish harvest technologies for circular tanks."