## Not run:# abstract foundcr_abstract('10.1109/TASC.2010.2088091')cr_abstract("10.1175//2572.1")cr_abstract("10.1182/blood.v16.1.1039.1039")# doi not found# cr_abstract(doi = '10.5284/1011335')# abstract not found, throws error# cr_abstract(doi = '10.1126/science.169.3946.635')# a random DOI# cr_abstract(cr_r(1))## End(Not run)