Which preposition to use with yost

at Occurrences 1%

The Medium's body was distinctly inclined toward Mr. Yost at the time.

in Occurrences 1%

He then drew the curtain (shown on the preceding page) along the cord (1, 2) and fastened it; placed three wooden chairs in front of the curtain, as indicated in the cut, and saying he needed to form a battery, asked Miss Agnes Irwin to sit in chair (d), and Mr. Yost in chair (c), the Medium himself sitting in chair (e).

of Occurrences 1%

I, therefore, think that makers of fine points, broad points, medium points, &c., may rest securely in their pens, notwithstanding a Yost of typewriters, Remington, or what not.

Which preposition to use with  yost