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:
| Outcome | Date | Tournament | Surface | Partner | Opponents in the final |
| --- | --- | --- | --- | --- | --- |
| Runner-up | 1968.0 | Barcelona , Spain | Clay | José Mandarino | Carlos Fernández Patricio Rodríguez |
| Runner-up | 1969.0 | London/Queen's Club , U.K. | Grass | Ove Nils Bengtson | Owen Davidson Dennis Ralston |
| Runner-up | 1971.0 | Salisbury , U.S. | Carpet | Clark Graebner | Juan Gisbert, Sr. Manuel Orantes |
| Winner | 1971.0 | Macon , U.S. | Hard | Clark Graebner | Željko Franulović Jan Kodeš |
| Runner-up | 1971.0 | Hampton , U.S. | Hard (i) | Clark Graebner | Ilie Năstase Ion Țiriac |
| Winner | 1971.0 | Caracas , Venezuela | Clay | Edison Mandarino | Gerald Battrick Peter Curtis |
| Runner-up | 1972.0 | Washington, D.C. , U.S. | Carpet | Clark Graebner | Tom Edlefsen Cliff Richey |
| Runner-up | 1974.0 | Gstaad , Switzerland | Clay | Roy Emerson | José Higueras Manuel Orantes |
| Winner | 1975.0 | Istanbul , Turkey | Outdoor | Colin Dibley | Colin Dowdeswell John Feaver |
| Runner-up | 1982.0 | Itaparica , Brazil | Carpet | Jose Schmidt | Givaldo Barbosa João Soares |
| Runner-up | 1983.0 | Bahia , Brazil | Hard | Ricardo Cano | Givaldo Barbosa João Soares |
Question:
Tell me the opponents for runner-up and surface of grass
Answer:
Owen Davidson Dennis Ralston