Vertices. ... To create a new vertex, change to EditMode, hold down CTRL, and click with the LMB. Of course, as a computer screen is two-dimensional, Blender can't determine all three vertex coordinates from one mouse click, so the new vertex is placed at the depth of the 3D cursor 'into' the screen.

Inkscape

Downloading Inkscape tonight. Hope it works live every other source program.

The forums say "If the content contained in the PDF is already in vector format, import it into Inkscape. Save as  a SVG and import the SVG into Blender."

or
"Convert the PDF to a format the Blender can read. Maybe trace it in Inkscape and save as SVG file"

Hmm

Dorothea Lange

Maynard Dixon