When a word and number appear together -- Section 15, Chapter 12, page 3 -- this is called a sequential reference. The number is always in a figure, and the word describing what it is is capped. There are a few exceptions: page, line, paragraph, verse, and size.
...on page 5
...in verse 14
...in line 7
...in Chapter 15
...in Row 17
...in Section 12
Happy punctuating!
Margie