1864, , , Mr. Sludge, "The Medium", Out of the drift of facts, whereby you learn What some was, somewhere, somewhen, somewhy?
1891, Thomas Hardy, Tess of the d'Urbervilles - A Pure Woman Chapter XXXVI, Yes, though nobody else should reproach me if we should stay together, yet somewhen, years hence, ...
2008, Michael F. Wagner, The Enigmatic Reality of Time Chapter Chapter One, … things always exist or occur somewhen as well. They exist or occur whenever — at whatever times-when — they in fact exist or occur, and not somewhen else.