Search for your projection. There are multiple options for both your projections, so you'll have to investigate each one carefully. You can click the "Well Known Text as HTML" link to see the individual parameter values.
When you've found the right one, click its "Proj4" link and copy the text that appears in your browser.
In QGIS, choose Settings > Custom CRS from the menu bar.
Click the icon that looks like a star, which creates a new CRS.
Paste the text you copied into the Parameters box.
Type a name in the Name box.
Click the icon that looks like a floppy disk, which saves the CRS.