Source: The Soviet Socialist Republic of Iran, 1920-1921: Birth of the Trauma by Cosroe Chaqueri, University of Pittsburgh Press, Pittsburgh and London, 1995.

It has this on Sultanzade in the Appendix (p. 476):

Sultanzade (Mikailian), Avetis (b. 1889)

Avetis Sultanzade, Haidar Khan's arch opponent in the Iranian Communist party, was not Muslim, nor was he merely a revolutionary practitioner; he was an intellectual and theoretician. Of an Armenian mother, he was born in 1889 into a poor family of the Marâqeh region. After five years of study in his native town, he went to the Armenian ecclesiastical school, Jamârân, at Ejmeyasin near Yerevan. On graduating, he joined the labour movement in the Caucasus and became a member of the Bolshevik faction of the Russian Social Democratic Workers party.

After the October revolution, he worked for the Soviet government. In 1919, like Haidar Khan, he was sent to Central Asia to mobilise Iranian workers for the ICP. There he recruited Iranian emigrants for the Iranian Red Army and organised the Tashkent 'Adalat conference and the ICP's congress in Anzali. His theoretical and political contributions constituted the ICP's main line of action until his withdrawal in 1922. He led the party's radical wing and called for immediate land reform in [the province of] Gilan. He disagreed with those who collaborated with Kuchek Khan.

Away from leading positions in the ICP and the Communist International, he worked for the Soviet banking system until 1927. At this time, the radical turn of the Comintern permitted his return to the ICP, which he reorganised and led until it was dismantled by the Soviets in 1932. He was then censured as a "deviationist anti-Leninist" by the Stalinist ideological apparatus. Nevertheless, he continued to battle with the Comintern and the Soviet bureaucracy until 1935, when he denounced those in charge of Iranian affairs in the Comintern. On July 16, 1938, he was shot as a "German agent," but his reputation was rehabilitated during the Khrushchev era.

Sultanzade was the author of numerous articles and books on varied subjects, but due to Stalinist repression, he remained quite unknown until the mid-seventies. His works on Iran and the East were quite novel and remain today a valuable source for the study of Iran's political and economic situation in the early twentieth century.(67)

Footnote 67 on p 612:
See C. Chaqueri, "Sultanzade: The Forgotten Revolutionary Theoretician of Iran: A Biographical Sketch," Iranian Studies 2-3, (1984); for Sultanzade's works see Historical Documents: The Workers', Social Democratic, and Communist Movement in Iran, ed. C. Chaqueri (Florence and Tehran, 1969-1994), vols. 4, 8, 20; Le Mouvement Communiste en Iran (Florence, 1979; and Sultanzade, The Forgotten Theoretician (Life and Works), ed. C. Chaqueri (Paris, 1985).