def cross_reference(self, model: BDF) -> None: """ Cross links the card so referenced cards can be extracted directly Parameters ---------- model : BDF() the BDF object """ msg = ', which is required by CSSCHD sid=%s' % self.sid self.aesid_ref = model.AESurf(self.aesid, msg=msg) self.lalpha_ref = model.AEFact(self.lalpha, msg=msg) self.lmach_ref = model.AEFact(self.lmach, msg=msg) self.lschd_ref = model.AEFact(self.lschd, msg=msg)