The manually annotated 'reference' atlas, published on the web and in print: H.W. Dong, The Allen Reference Atlas, (Book + CD-ROM): A Digital Color Brain Atlas of the C57BL/6J Male Mouse, Wiley, 2008. This atlas has been symmetrized with respect to the midline.
The volumetric atlas, in which each brain region is represented by a set of closed volumes. This atlas is used to initiate coordinate- or structure name based queries into the AGEA gene expression database.
On display here is the second variant of the atlas. The manually annotated sections can be viewed using the "AllenAtlas" plugin.
The volumetric atlas also features in Allen Brain Institute's stand-alone software package BrainExplorer, and in the multi-resolution atlas project Whole Brain Catalog.