my join function doesn't work

I am trying to combine several author names semicolon delimited into one cell. The input are author names that are placed in individual cells. To illustrate the question I added an Excel sheet.

I have a large number of rows with varying numbers of cells containing authors that I all want to combine in this fashion.

I tried to solve the problem with the join function, but run into trouble. I can't resolve the error. It would be great if somebody could help me out.

Below is what I tried.

Range("F1") = Join("A1:C1", ";")