Hölder's Inequality for Sums/Finite

Hölder's Inequality for Sums: Finite Form
Let $p, q \in \R_{>0}$ be strictly positive real numbers such that:
 * $\dfrac 1 p + \dfrac 1 q = 1$

Let $\GF \in \set {\R, \C}$, that is, $\GF$ represents the set of either the real numbers or the complex numbers.

Let $n \in \N_{>0}$ be a non-zero natural number.

Let $\sequence {x_k}_{1 \mathop \le k \mathop \le n}$ and $\sequence {y_k}_{1 \mathop \le k \mathop \le n}$ be finite sequences in $\GF$.

Then:
 * $\ds \sum \limits_{k \mathop = 1}^n \size {x_k y_k} \le \paren {\sum_{k \mathop = 1}^n \size {x_k}^p}^{1 / p} \paren {\sum_{k \mathop = 1}^n \size {y_k}^q}^{1 / q}$

where the summations are finite.