Reduced relative clauses

There is usually not a clear distinction between reduced relative clauses (RRC) and participial clauses (IP-PPL)

( (IP-MAT (CONJ og-og)
	  (NP-SBJ *con*)
	  (DOPI gerist-gera)
	  (NP-PRD (NPR-N Bartholomeus-bartholomeus))
	  (, ,-,)
	  (IP-MAT-PRN (NP-SBJ (PRO-N það-það))
		      (BEPI er-vera)
		      (NP-OB1 (N-N sonur-sonur)
			      (RRC (VAG upphaldandi-upphalda)
				   (NP-OB1 (NS-D vötnum-vatn)))))
	  (, ,-,)