free c:channel.
free a:bitstring.
free b:bitstring.

event A(bitstring).
event B(bitstring).
event C.

query i:time, j:time, k:time, x:bitstring; event(A(x))@i && inj-event(B(x))@j ==> inj-event(C)@k || inj-event(C)@k.

query i:time, j:time, k:time, x:bitstring; event(A(x))@i && inj-event(B(x))@j ==> inj-event(C)@k || inj-event(C)@k && inj-event(C)@k.

process
  event C;
  event A(a);
  event A(b);
  event B(a);
  event B(b)

(* EXPECTPV
Error: Time variable also assigned at File "examplesnd/lemmas/temporal_query10.pv", line 11, character 132.
xtime: error in child process (status : 2)
END *)
