You use your calibrated glassware as your reference. You can write an in-house calibration procedure and "calibrate" your other glassware to the one you have a calibration cert for. The calibration cert for the calibrated glassware should provide the traceability link you need for backward traceability to the standard the cal lab used for their calibration.
NOTE: I am not a calibration specialist with regard to glassware such as beakers, thermometers and such, so my reply is a general one.
Marc is correct. However, for the internal calibration to be traceable, you must also calculate the uncertainty of your measurements. Understand that volumetric, gravimetric, and photometric have different limits and different uncertainty contributions.