1831 P. O. Skene in 185 The further reduction of these 8 classes into 3..may be performed by any one who will remark the uniformity of the root-vowel.
1922 20 197 The nil-grade of the root vowel is represented by OE -tyllan (in fortyllan ‘to seduce’).
1998 74 157 The root vowel of /táandk-i-a/ shortens because it is in pre-antepenultimate position.