private static void checkIfAlreadyExistsOneDegreeWithSameAcronym(DegreeUnit degreeUnit) {
   for (Unit unit : UnitUtils.readInstitutionUnit().getAllSubUnits()) {
     if (!unit.equals(degreeUnit)
         && unit.isDegreeUnit()
         && degreeUnit.getAcronym().equalsIgnoreCase(unit.getAcronym())) {
       throw new DomainException("error.unit.already.exists.unit.with.same.name.or.acronym");
     }
   }
 }