@ARTICLE{
author={Shapovalova Alla I,Popovic Luka C,Afanasiev VL,Ilic Dragana J,Kovacevic Andjelka B,Burenkov Alexander N,Chavushyan Vahram H,Marceta-Mandic Sladjana,Spiridonova O,Valdes JR,Bochkarev Nikolai G,Patino-Alvarez V,Carrasco L,Zhdanova VE},
year={2019},
title={Long-term optical spectral monitoring of a changing-look active galactic nucleus NGC 3516-I. Continuum and broad-line flux variability},
journal={MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY},
volume={485},
number={4},
pages={4790-4803},
document_type={Article},
} 

@ARTICLE{
author={Shapovalova Alla I,Popovic Luka C,Chavushyan Vahram H,Afanasiev VL,Ilic Dragana J,Kovacevic Andjelka B,Burenkov Alexander N,Kollatschny Wolfram,Spiridonova O,Valdes JR,Bochkarev Nikolai G,Patino-Alvarez V,Carrasco L,Zhdanova VE},
year={2017},
title={Long-term optical spectral monitoring of NGC 7469},
journal={MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY},
volume={466},
number={4},
pages={4759-4775},
document_type={Article},
} 

@ARTICLE{
author={Shapovalova Alla I,Popovic Luka C,Chavushyan Vahram H,Burenkov Alexander N,Ilic Dragana J,Kollatschny Wolfram,Kovacevic Andjelka B,Valdes JR,Patino-Alvarez V,Leon-Tavares J,Torrealba J,Zhdanova VE},
year={2016},
title={First Long-Term Optical Spectral Monitoring of a Binary Black Hole Candidate E1821+643. I. Variability of Spectral Lines and Continuum},
journal={ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES},
volume={222},
number={2},
pages={-},
document_type={Article},
} 

@ARTICLE{
author={Shapovalova Alla I,Popovic Luka C,Collin S,Burenkov Alexander N,Chavushyan Vahram H,Bochkarev Nikolay G,Benitez E,Dultzin D,Kovacevic Andjelka B,Borisov N,Carrasco L,Leon-Tavares J,Mercado Abelardo,Valdes JR,Vlasuyk VV,Zhdanova VE},
year={2008},
title={Long-term variability of the optical spectra of NGC 4151 - I. Light curves and flux correlations},
journal={ASTRONOMY & ASTROPHYSICS},
volume={486},
number={1},
pages={99-U81},
document_type={Article},
}