ON A GAUGE-GENERALIZATION OF A NON-LINEAR SIGMA-MODEL WITH NONVANISHING HOPF INVARIANT Статья KUNDU A. Canadian Journal of Physics. Canadian Science Publishing. Том 59. 1981. С. 1609-1613
NEW DATA ON THE GEOLOGY OF THE WEST HIMALAYAS Статья AZHGIREI G.D., UMNOVA N.I., SINHA A.K. Doklady Akademii nauk SSSR. Mezhdunarodnaya Kniga, Moscow, Russian Federation. Том 260. 1981.