Constellation names (used for Bayer and Flamsteed designations of bright stars: alf Lyr, for variable stars: RS CVn, for novae: Nova Her 1991, etc.) must be written using the following abbreviations:
And Ant Aps Aqr Aql Ara Ari Aur Boo Cae Cam Cnc CVn CMa CMi Cap Car Cas Cen Cep Cet Cha Cir Col Com CrA CrB Crv Crt Cru Cyg Del Dor Dra Equ Eri For Gem Gru Her Hor Hya Hyi Ind Lac Leo LMi Lep Lib Lup Lyn Lyr Men Mic Mon Mus Nor Oct Oph Ori Pav Peg Per Phe Pic Psc PsA Pup Pyx Ret Sge Sgr Sco Scl Sct Ser Sex Tau Tel Tri TrA Tuc UMa UMi Vel Vir Vol Vul LMC SMC
Constellation limits are given by the catalogue VI/42. This query page gives also access to a function allowing to derive the name of a constellation from a position on the sky.