Editing Reciprocal polynomial (section)

===Real coefficients===
A polynomial with [[Real number|real]] coefficients all of whose [[Complex number|complex]] roots lie on the unit circle in the [[complex plane]] (that is, all the roots have modulus 1) is either palindromic or antipalindromic.<ref>{{cite book|first1=Ivan|last1=Markovsky|first2=Shodhan|last2=Rao|title=2008 16th Mediterranean Conference on Control and Automation |chapter=Palindromic polynomials, time-reversible systems, and conserved quantities |publisher=IEEE|pages=125–130|year=2008|doi=10.1109/MED.2008.4602018|isbn=978-1-4244-2504-4|s2cid=14122451 |url=https://eprints.soton.ac.uk/266592/1/Med08.pdf}}</ref>