Squarate and croconate in designing one- and two-dimensional oxamidato-bridged copper(II) complexes: synthesis, crystal structures and magnetic properties of 〚Cu 2 (apox)(C 4 O 4 )(H 2 O) 2 〛 n · n H 2 O and 〚Cu 4 (apox) 2 (C 5 O 5 ) 2 〛·6 H 2 O | Publicación