Only later did it become known that an equivalent formula had been published in Russia by Dokshitzer also in 1977 and Gribov and Lipatov already in 1972.
Only later did it become known that an equivalent formula had been published in Russia by Dokshitzer also in 1977 Yu.L. Dokshitzer. JETP 46:641 (1977) and Gribov and Lipatov already in 1972.