1 Samuel 31:8

And it came to pass on the morrow, when the Philistines came to strip the slain, that they found Saul and his three sons fallen in mount Gilboa.

Cross-reference

1 Chronicles 10:8 gives the identical account of Philistines finding Saul's body the next day — a direct parallel.

2 Samuel 1:19 is David's lament over Saul and Jonathan's death on Mount Gilboa — the same event mourned poetically.