Search for "Popov L.N." or the Russian title "Лабораторные испытания строительных материалов" . It is frequently mirrored here in both DJVU and PDF formats.
Similar to Libgen, searching for the ISBN or title in Russian often yields the 1984 "Vysshaya Shkola" edition.
Since the file is in , you will need a specific reader to open it: WinDjView: The most popular lightweight reader for Windows.
You can also find "DjVu Viewer" extensions for Chrome or Firefox if you prefer not to install standalone software.
You can find the DJVU file for (1984) by L.N. Popov through several specialized digital libraries and technical archives. This 168-page manual is a standard reference for construction material testing procedures. Where to Find the DJVU File