Temperature setting in an office?

I work in an office that is a combination of a large room with four cubicles and also has several small office off this large room. I am having an issue with 2 of the 3 co-workers who share the cubuicle space with me. They have been keeping the temperature controls at 68 degess (winter and summer) even this temperature is still to hot for them so they open the door so the cold air from the garage comes in as well making it less than 68 degree. I have a space heater under my desk but that does not keep my upper body warm. my fingers get so cold that I have trouble concentrating. I have asked that they keep the temperature at 72 and not open doors while the heat/air is on. My question is this - Is it unreasonable for me to make this request? I am getting no where with these two and have informally brought our supervisor into the discussion with no resolution. I have now requested a formal discussion with all parties involved. It will take place one week from today.

I did want to add that all parties involved are women so the issue of men liking cooler temperatures does not apply here.

You are definitely not being unreasonable. 68 degrees is too cold for any office, even here in Texas. I work for an HVAC contractor. The A/C system here in the office stays set at a constant 76 deg year round, even if it is 102 deg outside.
Most A/C systems are not designed to be cranked down to anything lower than 72 deg without it icing up or causing other problems. If the A/C system is running while iced up it can be damaged or destroyed. If the system manages to continue running in that condition it will not be operating properly or as efficiently as possible. An A/C system is designed to heat/cool only a certain amount of room volume. Cooling any volume greater than what it was designed for is overload which will cause the A/C system to run constantly...very inefficient plus creates huge electric bills. Your fussy coworkers who keep the doors open while the A/C system is running are in fact overloading it which means it is working much harder than necessary and not really heating or cooling anything. You'll notice the same sort of thing in your own home if you run the A/C system while the front door is wide open.

Not unreasonable, except that you are OUT NUMBERED!

Can you move to the farthest cube?

Wear a sweater, run the space heater, and pray for an early summer. Or, quit, before you are fired for causing such a lot of arguments, wasting everyone's time.

You are expected to show initiative and fairness in finding a solution that shows your superior ability to act with personal responsibility and kindness towards everyone.

This is actually an opportunity for PROMOTION through demonstrating your ability to create compromises!

I worked in a place that desided the best way to prevent illness, was to have the air conditioner on during the winter in Michigan!

You will never win the battle if you work with constant complainers.

What I did was I brought a heating pad to work and wore three sweaters and gloves. After a while I quit the job.

If you don't work in extreme environment and all you are argueing about is a difference of 3 degree, then change your attire and bring warming elmiates. choose your battles wisely!