Except in the case of fraud, intent to evade this part or regulations adopted pursuant thereto, or failure to make a return, every notice of deficiency determination shall be served within three years after the 25th day of the month following the period for which the return was due or within three years after the return was filed, whichever period expires later. In the case of failure to make a return, the notice of determination shall be served within eight years after the date the return was due.