Fig. 4
From: PUG-View: programmatic access to chemical annotations integrated in PubChem
Retrieval of annotation attachments. Some annotations collected from authoritative sources are file attachments. Retrieving these attachments through PUG-View is a two-step process. In a first PUG-View request, the internal identifier for an attachment is obtained. This identifier is used in a second PUG-View request to retrieve the attachment. The “…” in the figure above refers to the PubChem web address “http://pubchem.ncbi.nlm.nih.gov”, which is omitted