The choice of the Housekeeping genes, depends on a variety of factors such as, the tissue you are working on, the species and the most important the experimental conditions. By your question I suppose that you are working with neural tissue, since one of your target gene is GFAP (Glial Fibrillary Acid Protein), a glial marker and GLT1. If this is true, the choice of your housekeeping genes depends on whether you are working with a post mortem tissue or not, because it has been reported that in some specific condition, as post mortem tissues, the expression of housekeeping genes might change.
In the post mortem brain tissue it has been reported that CYC1 AND EIF4A2 are good housekeeping genes because their expression remain stable even in post mortem tissues. Otherwise, GAPDH or Beta Actin would be fine, if you are not working on post mortem tissue conditions