Run-in
headerStart of block. The run-in header
should be inside the border around this block and there should be no
space between the word "header" and the word "Start". The border of the
run-in must have no vertical part on the left in the first line and no
vertical part on the right in the second line. It must have a vertical
part on the right in the first line and a vertical part on the left in
the second line. The border of the run-in must not extend outside the
border of the block.