ɐ nˈaɪntiːnhˈʌndɹɪd nˈaɪnti θɹˈiː pˈeɪpɚɹ ɪn lˈeɪbɚɹ ˌiːkənˈɑːmɪks ˈɑːɹɡjuːd ðæt lˈæstɪnfˈɜːstˈaʊt lˈeɪɔf ɹˈuːlz mˈiːnz ðæt jˈuːniən ɪndˈɪfɹəns kˈɜːvz ɑːɹ lˈoʊkəli hˌɔːɹɪzˈɔntəl.
A 1993 paper in Labour Economics argued that last-in-first-out layoff rules means that union indifference curves are locally horizontal.