origin = ( 2,4.0)
	boxht = boxht/2;  minax = minax/2
	arrowlen = arrowlen/2
	majax = 1.25*majax
doc:	ellipse 'document'
	arrow ->
	box  'REFER'

	spline -> \
	    downright 0.75*boxht \
	       to doc.south + ( 0,-boxht ) \
	         to doc.south + ( 0.75*boxwid, -(boxht*1.25) )

	right
tbl:	box 'TBL' 
	arrow -> 
	box  'EQN'

	spline -> \
	    downright 0.75*boxht \
	       to tbl.south + ( -boxwid*0.25, -(1.1*boxht) ) \
	         to tbl.south + ( 0.75*boxwid, -(boxht*1.35) )

	right
	box 'TROFF'
	arrow ->
	ellipse 'typesetter'