With no explanation, label text_A→text_B with either "not-entailed" or "entailed".
text_A: Ethiopia 's annexation of Eritrea as a province 10 years later sparked a 30-year struggle for independence that ended in 1991 with Eritrean rebels defeating governmental forces ; independence was overwhelmingly approved in a 1993 referendum .
text_B: 1993 is a calendar year
entailed.