Where can I find the multiple node block

[Oreos]

I am looking for the symbol that takes the negative and positive peakc and outputs one signal to measurement file:

Figure 4.

http://zone.ni.com/devzone/cda/tut/p/id/4644#toc1 

[smercurio_fc · Accepted solution]

If you're referring to the small yellow block between the big two blue blocks on the right-hand side of Figure 4 of that document, then that's the Merge Signals function. It should be in the Express -> Signal Manipulation palette.