THE ESSENTIAL SPECTRUM OF THE SCHRÖDINGER OPERATOR FOR A THREE-PARTICLE SYSTEM WITH MASSES m1 = M2 = c∞ AND m3 < ∞. INNOIST [Internet]. 2025 Jun. 15 [cited 2025 Jun. 17];2(6):678-87. Available from: https://www.innoist.uz/index.php/ist/article/view/1052