His "Theoretical Foundations of Multiple Telephony" was published in 1907 in the "Elektrotechnische Zeitschrift" and then, in 1914, "The Use of High-Frequency Alternating Currents in Telegraphy, Telephony and for Power Transmission" was published in "The Electrician."
Fundamentele teoretice ale telefoniei multiple au fost publicate în 1907 în revista „Elektrotechnische Zeitschrift” și apoi, în 1914, în lucrarea „The use of High-Frequency Alternating Currents in Telegraphy, Telephony and for Power Transmission” publicată în revista “The Electrician”.