Effect of Vildagliptin on Glucagon Concentration During Meals in Patients with Type 1 Diabetes - Foley, J. E.; Ligueros-Saylan, M.; He, Y.-L.; Holst, J. J.; Deacon, C. F.; Dunning, B. E.; Leone-Jones, A.; Yu, T.; Kelley, D. E. (Hormone and Metabolic Research, 2008)