It can be assumed that it is a New Testament reference for the book of Matthew, but the syntax used raises doubts because it is not the classic 16: 15 for chapter 16; verse 15. Or maybe you can have an error and omission, and be ?? : 15-16 , which would be the chapter ??; verses 15 through 16.
In Matthew 16:15-17 we find the following biblical account: "And you, who do you say I am?" asked them. To which Simon Peter replied, "You are the Christ, the son of the living God." Then Jesus said to him, "Blessed are you, Simon, son of Jonah, for this was not revealed to you by flesh and blood, but by my father who is in heaven.