This is a test file with some referenced equations, line
$$ this \qquad(1)$$

Some equations might be inside of text, $$ for example \qquad(2)$$ this
one.

Some equations might be on start of paragraphs:

$$ start \qquad(3)$$ of paragraph.

Other might be on separate paragraphs of their own:

$$ separate \qquad(4)$$

Some of those can be labelled:

This is a test file with some referenced equations, line
[$$ this \qquad(5)$$]{#eq:0}

Some equations might be inside of text,
[$$ for example \qquad(6)$$]{#eq:1} this one.

Some equations might be on start of paragraphs:

[$$ start \qquad(7)$$]{#eq:2} of paragraph.

Other might be on separate paragraphs of their own:

[$$ separate \qquad(8)$$]{#eq:3}

Then they can be referenced:

Individually eq. 5, eq. 6, eq. 7, eq. 8

Or in groups eqns. 5, 6, 8

Groups will be compacted eqns. 5-8