Question: Which magazine maintains the ranking of fighters in the weight class which Joanna Jędrzejczyk competes within?

<P0-S0> Joanna Jędrzejczyk (] ; born August 18, 1987) is a Polish mixed martial artist and former Muay Thai kickboxer who competes in the women's strawweight division of the Ultimate Fighting Championship. <P0-S1>  She is the current UFC Women's Strawweight Champion and the third European (and only Polish) champion in UFC history after Bas Rutten in 1999 and Andrei Arlovski in 2005. <P0-S2>  As of May 2017, she is the consensus #1 female strawweight, and #1 pound-for-pound female MMA fighter in the world. <P0-S3>  She is also currently the #8 pound-for-pound fighter in the UFC mixed gender rankings, making her the top female on the list. <SEP> <P1-S0> Ekaterina Vandaryeva (born January 20, 1991) is a Belarusian kickboxer who defeated future UFC champion Joanna Jędrzejczyk in a controversial judges' decision to become the WKN champion in 2011. <SEP> <P2-S0> Pound for pound is a ranking used in combat sports, such as boxing or mixed martial arts, of who the better fighters are relative to their weight (i.e., adjusted to compensate for weight class). <P2-S1>  As these fighters do not compete directly, judging the best fighter pound for pound is subjective, and ratings vary. <P2-S2>  They may be based on a range of criteria including "quality of opposition", factors such as how exciting the fighter is or how famous they are, or be an attempt to determine who would win if all those ranked were the same size. <P2-S3>  In boxing, the term was historically associated with fighters such as Benny Leonard and Sugar Ray Robinson who were widely considered to be the most skilled fighters of their day, to distinguish them from the generally more popular (and better compensated) heavyweight champions. <P2-S4>  Since 1990, "The Ring" magazine has maintained a pound for pound rank of fighters. <P2-S5>  ESPN.com has a list for mixed martial artists. <P2-S6>  In December 2013, Ronda Rousey became the first woman to appear on the top 10 of a mixed-gender major publication. <SEP> <P3-S0> In combat sports where champions are decided by a challenge, the lineal championship of a weight class is a world championship title held initially by an undisputed champion and subsequently by a fighter who defeats the reigning champion in a match at that weight class. <P3-S1>  In professional boxing, the lineal champion is informally called "the man who beat the man". <P3-S2>  Champions recognized by sanctioning bodies such as the World Boxing Association (WBA) or World Boxing Council (WBC), or the Ultimate Fighting Championship (UFC) may vacate their title voluntarily, or be stripped of the title for breaching the sanctioning body's regulations or contracts. <P3-S3>  There will thus be a breach of continuity in the list of sanctioned champions which the lineal championship is intended to prevent. <P3-S4>  However, there is no single canonical list of lineal champions at any weight class, because there is no agreed upon method of determining the starting point for each lineage and conflicting opinions on what to do when the current champion retires or moves to a different weight class, although there is agreement that any stripping of a title be discounted.