As a military pilot, our regulations listed things that disqualified airports as being alternates. I have not been able to find a reference to these same items listed in the 14 CFR Part 91. Does anyone know where to find the regulatory references for the list of things that disqualify an airport as an alternate for an IFR plan? For example, an airport cannot be used as an alternate if the instrument approach at the airport you plan to use is listed as "Radar Required." Is that a consideration in General Aviation? Likewise, I was trained that if a navaid is unmonitored or if the airfield only has GPS approaches, again disqualifies the airfield as an alternate. However, I don't know where that is written in the FARs. Does anyone know where I should look?