How to download a database of bibliographic information for all published scientific papers?
Probably the closest you can get is the Open Academic Graph, a graph-based database of about 321 million papers (I don't think the actual papers are stored, but all the information you want is there). You can download all the 143 GB of data from the above link, but do note that because it's a merge of two existing graph-based paper databases (Microsoft Academic Search and AMiner) there are going to be a lot of duplicates.