In an attempt at overcoming these limitations, from the late
eighties onward, a series of prototypes have been developed that
seek to improve the visualization of results from journal and digital
library portals. Some have focused on the representation of the
content of the retrieved documents (Hearst, 1995; Egan et al., 1989;
Weiss-Lijn et al., 2001; Woodruff et al., 2001; Lam and Baudisch,
2005; Hoeber and Yang, 2006; Nualart and Pérez-Montoro, 2013);
while others have contributed new interactive visualizations of the
set of results after formulating the search query.