The Nobel Prize in Physics 1928 was awarded to Owen Willans Richardson "for his work on the thermionic phenomenon and especially for the discovery of the law named after him".
Owen Willans Richardson received his Nobel Prize one year later, in 1929. During the selection process in 1928, the Nobel Committee for Physics decided that none of the year’s nominations met the criteria as outlined in the will of Alfred Nobel. According to the Nobel Foundation's statutes, the Nobel Prize can in such a case be reserved until the following year, and this statute was then applied. Owen Willans Richardson therefore received his Nobel Prize for 1928 one year later, in 1929.