There are 10 isomers altogether. First all the cis isomers: the first three display the three possible linkage isomers, the next two are ionization isomers of the first three. Note how the sulfate ion is written (OSO₃) to emphasize the bonding through oxygen, even though sulfate is not an ambidentate ligand.

And now the 5 trans isomers:

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Created January 20 1001 by M. F. Richardson
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