Mahabharata 12.84.54

आरुह्य वातायनमेव शून्यं; स्थलं प्रकाशं कुशकाशहीनम्वागङ्गदोषान्परिहृत्य मन्त्रं; संमन्त्रयेत्कार्यमहीनकालम्

āruhya vātāyanameva śūnyaṃ; sthalaṃ prakāśaṃ kuśakāśahīnamvāgaṅgadoṣānparihṛtya mantraṃ; saṃmantrayetkāryamahīnakālam

Our plain-language meaning of this verse is waiting for scholar review.