Structural, magnetic and electric-polarization properties of geometrically frustrated YBaCo4O7and DyBaCo4O7cobaltitesC. Dhanasekhar, A. K. Das, A. Das, S. K. Mishra, R. Rawat and A. VenimadhavEPL, 127 6 (2019) 67001DOI: https://doi.org/10.1209/0295-5075/127/67001