Any organization of certificated employees of Community College District No. 20 desiring to be recognized as the majority organization representing such employees pursuant to chapter 143, Laws of 1965, RCW 28.72.010 — 28.72.090, shall request in writing of the board of trustees of Community College District No. 20 that an election be held to determine whether a majority of such employees desire to designate it as their representative for the purpose of the act. Upon the receipt of such a request the board of trustees of the Community College District No. 20 will request some independent and neutral person or association to determine whether thirty percent or more of the certificated employees of Community College District No. 20 have indicated that they desire to be represented by that organization for such purposes. The independent and neutral person or association shall make such determination upon the basis of records of dues, paying memberships, signed authorizations to represent, or other reliable and probative evidence.