Instead of .*? you need to use something more complex, something that can handle quoted strings. Something like:
my $term = qr/"[^"\\]*(?>\\.[^"\\]*)*"|[^,"]*/;
(which can handle escaped (backslashed) contents, too, change to
my $term = qr/"[^"]*(?>""[^"]*)*"|[^,"]*/;
if you escape quotes by doubling them)

And then you can do

/^$term,$term,$term,($term)/o;
which seems to work well for me... BTW it's "while", not "While".
my $term = qr/"[^"\\]*(?>\\.[^"\\]*)*"|[^,"]*/; while (<DATA>) { /^$term,$term,$term,($term)/o and print "$1\n"; } __DATA__ 6,0,3,"8.1",1 7,578,,"8.2,r1",1 8,0,5,"8.2,r3",1 18,0,13,"6.2",1 19,D610,,"6.3,r1",1 20,2f78,15,"6.3,r2",1
Result:
"8.1"
"8.2,r1"
"8.2,r3"
"6.2"
"6.3,r1"
"6.3,r2"

In reply to Re: Nth match. by bart
in thread Nth match. by xiaoyafeng

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