Hello Pahl and All,

> Is honey production greater than having two separate hives?

Research done by Dr. Farrar showed it was although like most beekeeping
topics there are those which would argue otherwise. Dr. Farrar had around
400 two queen hives in operation at one time I believe.

> Can the entrances of the two hives be on the same side?
Yes.
Forget the idea of two hives and only consider one large hive WITH two
queens.  After the honey flow starts the second queen is a liability instead
of an asset if interested in honey production as the bees raised  later
will arrive too late to help with the honey flow.

> Do the strength of the two hives need to be similar?
no.
>
> I would be interested in receiving internet links to get more information,

Maybe others will provide internet sites as I have spent all the time I dare
spend on the net today. . Quite a bit has been written about two queen
hives. There are more con's about two queen hives than pro's in my opinion
but fun to play with if you do not mind getting a few stings. 100,000 bees
on a hot day without a honey flow on can be quite testy. Add 24 in the yard
and the problem gets worse.
Beekeeping story:
I had some two queen hives  in plain sight of a busy road. One had fallen
over. A couple of new beekeepers from our club thought the would help out
and upright my hive for me. There was not a honey flow on.  Needless to say
the hive was not set back up and both received many stings. On rare
occasions I have had to walk away from strong two queen hives at peak
population right before the start of the honey flow. I also did a three
queen hive once from spring till fall.
The  fallen over hive had five deep boxes of brood and three deep boxes for
space (future honey crop). If 15,000 bees (without crowding) will fit in a
deep box then at least seven to eight would be needed for 100,000 bees. Dr.
Farrar used five 6 5/8 brood boxes and claimed 100,000 bees but also had
many
 6 5/8 supers in place.
Side by side has advantages but more disadvantages in my opinion.
Sincerely,
Bob Harrison