Donald J. Ruhl (1923 – 1945), American Marine; awarded Medal of Honor for action at Iwo Jima
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Henry Ruhl (? – 1945), American murderer; executed in Wyoming
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J. B. Ruhl (contemporary), American legal academic specializing in environmental law
Sarah Ruhl | J. B. Ruhl | Henry Ruhl | Donald J. Ruhl |
The final complete system came in 1927 when Berlin-based Max Ruhl and Ernst Neuman combined internal illumination and solenoid operation.