2016
KozkoSergeev - Problems with Parameters ru
    https://uchitel.by/catalog/book/400361
    34A74DA120C1B130DD31330FCB9B8664
    08AADDF27B9E2276411C56C63FB3765F
    8E2C635D2E5457D1A5E7946347B475F7
2004
Sergeev - Math Problems with Answers and Solutions ru
    9478BA46D1520A6472EE32B150C502FE
    2B8CFAE6FA5BED2484EFD6AE5A5D3FE3
    8D0A49584B8AE0B591C9892D687DECEC
    1EFA0A49E310C6FBD07584B0D2BC5889
2001
Sergeev - 1000 Math Questions and Answers 2nd ed ru
    7625F33781960344B2E8161715B5D98D
    FF32ABF8FDB9E602A97FA07DB50CD331
    DDA6D015D917FC2CA0EB01A5CEA94C9B
1998
SergeevMelnikov - Entrance Exam Problems 93-97 ru
    1EFA0A49E310C6FBD07584B0D2BC5889
1990
Sergeev - How to Solve Exam Problems ru
    A7F3D969C812626F2425AB1439737FB6
    B80CC105154DF3238FA25DC868673A15
    62603FE70E4606A968A576329EA300BE