Update MathSciNet journal abbreviation list

journals/journal_abbreviations_mathematics.csv

@@ -2305,6 +2305,7 @@
 "Memoirs of the Institute of Science and Engineering. Ritsumeikan University","Mem. Inst. Sci. Engrg. Ritsumeikan Univ."
 "Memoirs on Differential Equations and Mathematical Physics","Mem. Differ. Equ. Math. Phys."
 "Memorias de la Sociedad Matematica Mexicana","Mem. Soc. Mat. Mex."
+"Mens Agitat---Colloq.","Mens Agit.---Colloquia"
 "Meridian: Crossing Aesthetics","Meridian Crossing Aesthet."
 "Metalogicon. International Journal of Pure and Applied Logic, Linguistics and Philosophy. New Series","Metalogicon (N.S.)"
 "Methoden der Psychologie","Methoden Psych."