Peculiar features of the magnetic state of ensembles of magnetic nanoparticles of substituted manganites: experiment and model calculations - D. M. Polishchuk; Ju. O. Tikhonenko-Polishchuk; S. A. Solopan; A. V. Bodnaruk; N. N. Kulik; A. I. Tovstolytkin; A. N. Pogorelyj (Low Temperature Physics, 2017)