It depends on your source.
If it is a reputable ancillary company, they will make their Tamoxifen Citrate at 30.5mg/ml, which is the same dosage as a Nolva tab. It makes it have 20mg Tamoxifen. Some companies play off people's stupidity and dose at 20mg/ml Tamoxifen Citrate, despite knowing that the average user expects it to be 20mg/ml Tamoxifen, which is delivered as 30.5mg Tamoxifen Citrate.
And Pioneer, if you see ANYWHERE that has a tamoxifen without a citrate, you have seen an oddity, since even Nolva tabs have tamoxifen citrate.
http://www.rxlist.com/cgi/generic/tamox.htm
Scroll down to "description" at lower half of page.