
theorem po1:
for F being Field, E being FieldExtension of F
for L being F-monomorphic Field,
    f being Monomorphism of F,L
for p being Element of Ext_Set(f,E) holds p <= p
proof
let F be Field, E being FieldExtension of F;
let L be F-monomorphic Field;
let f be Monomorphism of F,L, p be Element of Ext_Set(f,E);
for K being FieldExtension of p`1, g being Function of K,L
      st K = p`1 & g = p`2 holds g is (p`2)-extending;
hence thesis by FIELD_4:6;
end;
