equation solving - How can Mathematica help me to find a real radical expression for roots of this polynomial?‎

The polynomial $P(x)=x^‎‏4‏‎-‎‏4‏x^‎‏2‏‎-‎‏2‏x+‎‏1$‏‎ has ‎‏4‏‎ real roots (this can be clearly checked by plotting). But solving $P(x)=‎‏0‏‎$, using Solve[x^‎‏4‏‎-‎‏4‏x^‎‏2‏‎-‎‏2‏x+‎‏1‏‎==‎‏0‏‎,x] leads to x=-‎‏1‏‎ and ‎‏3‏‎ other roots which (however they're ‎not) seems complex number as they are represented in terms of $i$ (the imaginary unit):‎

But I want to have the roots represented in a real closed radical expression. I mean neither in ‎trigonometric representation (such as the output of ComplexExpand[]) nor with any $i$'s in it. Is ‎there any simplification function or procedure that can help?‎ ‎ I've tried Simplify[] and FullSimplify[] and their various options. Even I've combined them with ‎some other expression manipulation functions such as Expand[], Refine[] and ComplexExpand[], ‎but I could not reach my goal.