Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| ILO code | Field | conclusion date | entry into force | closure for signature | Parties (April 2011) | Denunciations (September 2011) | revising convention(s) | text and ratifications |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| C5 | Industry | 28 November 1919 | 13 June 1921 | N.A. | 2.0 | 70.0 | C59, this convention | Text, ratifications |
| C7 | Sea | 7 July 1920 | 27 September 1921 | N.A. | 3.0 | 50.0 | C58, this convention, MLC | Text, ratifications |
| C10 | Agriculture | 16 November 1921 | 31 August 1923 | N.A. | 4.0 | 51.0 | this convention | Text, ratifications |
| C15 | trimmers and stokers | 11 November 1921 | 20 November 1922 | N.A. | 9.0 | 60.0 | this convention | Text, ratifications |
| C33 | Non-Industrial Employment (revised) | 30 April 1932 | 6 June 1935 | 29 December 1950 | 2.0 | 23.0 | C60, this convention | Text, ratifications |
| C58 | Sea (revised) | 24 October 1936 | 11 April 1939 | N.A. | 15.0 | 36.0 | this convention, MLC | Text, ratifications |
| C59 | Industry (revised) | 22 June 1937 | 21 February 1941 | 19 June 1976 | 9.0 | 27.0 | this convention | Text, ratifications |
| C60 | Non-Industrial Employment | 22 June 1937 | 29 December 1950 | N.A. | 0.0 | 11.0 | this convention | Text, ratifications |
| C112 | Fishermen | 19 June 1959 | 7 November 1961 | N.A. | 8.0 | 21.0 | this convention, Work in Fishing Convention | Text, ratifications |
Question:
What  was the revising convention of the field 'trimmers and stokers'?
Answer:
this convention