Name the landesliga mitte for fc gundelfingen and vfl frohnlach
create table table_20181270_3 (landesliga_mitte varchar, landesliga_süd varchar, landesliga_nord varchar, PRIMARY KEY (landesliga_mitte))
select landesliga_mitte from table_20181270_3 where landesliga_süd = "fc gundelfingen" and landesliga_nord = "vfl frohnlach"