Unable to find "Refer to the SMPP 3.4 specifications for additional details" document

[mache]

Hi,

In the Avaya Aura® Experience Portal 7.0.1 Documentation Library, for Change SMPP Connection page field descriptions, I can see the below information for most of the fields

Refer to the SMPP 3.4 specifications for additional details.

Please can anyone help me find where can I get the SMPP 3.4 specifications for additional details.

Regards