updates references

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 203050089 Sanchit Gupta 	sanchitsgiitb@cse.iitb.ac.in	Solved: Q3
 203050068 Sailendra Verma	sailendraverma@cse.iitb.ac.in 	Solved: Q4, Q6
 203059008 Samarth Joshi 	samarthjoshi@cse.iitb.ac.in 	Solved: Q1, Q5, Q6
-203050048 Roshan Sahu 		sroshan@cse.iitb.ac.in 		    Solved: Q2, Q5
+203050048 Roshan Sahu 		sroshan@cse.iitb.ac.in          Solved: Q2, Q5
 Gitlab Link: https://git.cse.iitb.ac.in/sroshan/SpartanBotsAssignment3
-References
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+References
+[1]https://vds-admin.ru/sed-and-awk-101-hacks/chapter-3-regular-expressions
+[2]https://stackoverflow.com/
+[3]https://www.gnu.org/software/gawk/manual/gawk.html
+[4]https://www.math.utah.edu/docs/info/gawk_5.html
+[5]https://www.grymoire.com/Unix/Sed.html