((CIAAW2017)) adds a full reference (<ref>...</ref>) for the standard atomic weight (Ar, standard) of chemical elements as defined by IUPAC (commission: CIAAW). The source citation is:
This template has options to use by refname, and as plain source (no <ref> tag). See #Options.
Notes
As CIAAW publishes the atomic weights biannually, in 2015 the website published a new list of standard atomic weights.[2] It appears that in 2015, only the formal standard atomic weight of ytterbium (70Yb) was changed.[3]
)CIAAW may publish changes to atomic weights (including its precision and derived values). Since 1947, any update this is done in odd years nominally; the actual date of publication may be some time later.