Snegourotchka 9, Fairy Spring's Aria.
g) Violas and Double basses in octaves.
This combination seldom arises and is only used when the 'cellos are otherwise employed.
Example:
[No. 31.] Legend of Kitesh 223.
h) Parts progressing in octaves, each part doubled in unison. Melodies situated in the middle orchestral range may be allotted to 1st and 2nd Vns, in octaves with Violas and 'Cellos. This arrangement is constantly found, and produces a beautiful quality of tone, somewhat severe in character.
Examples:
Snegourotchka 58, 60, 65 and 68. The same melody, played twice pianissimo, not doubled, then twice (mezzo-forte and forte), doubled in the wood-wind.
Mlada, Act II, the beginning of the Lithuanian dance. A lively piano theme.
Ivan the Terrible, Act II 28.