Original sentence: He was planning a similar type shooting at a high school west of Montreal.The Dawson school shooting seems to have ignited a wave of school shootings, in a similar manner to the "copycat" shootings following the Columbine Massacre
Edited sentence: He was planning a similar type shooting at a high school west of Montreal [14].The Dawson school shooting seems to have ignited a wave of school shootings,  in a similar manner to the "copycat" shootings following the Columbine Massacre