	versar vsr to buy marietta ml unit versar inc said it has agreed in principle to uire martin marietta corp s martin marietta environmental systems unit for about dlrs versar said it would use its working capital and an established life of credit to find the purchase which is subject to approval by both boards and is expected to be completed in april marietta environmental had revenues of about nine mln dlrs versar said the uisition should have a moderately favorable effect on its earnings this year reuter 
